Group-based acknowledgment feedback techniques for wireless communications

ABSTRACT

Methods, systems, and devices for wireless communications are described that support group-based acknowledgment feedback techniques. Two or more different groups of downlink transmissions may each have an associated group-based acknowledgment feedback, and a base station may transmit downlink control information to a UE that indicates one or more parameters that are used to determine which downlink transmissions are to be reported in the group-based feedback. Based on the parameters in the downlink control information, the UE may determine the feedback to be reported, and a timing for when to transmit the feedback to the base station.

CROSS REFERENCE

The present application for patent is a Continuation of U.S. patentapplication Ser. No. 16/894,542 by Khoshnevisan et al., entitled“GROUP-BASED ACKNOWLEDGMENT FEEDBACK TECHNIQUES FOR WIRELESSCOMMUNICATIONS” filed Jun. 5, 2020, which claims the benefit of U.S.Provisional Patent Application No. 62/887,887 by Khoshnevisan et al.,entitled “GROUP-BASED ACKNOWLEDGMENT FEEDBACK TECHNIQUES FOR WIRELESSCOMMUNICATIONS,” filed Aug. 16, 2019, and the benefit of IndianProvisional Patent Application No. 201941026827 by Khoshnevisan et al.,entitled “GROUP-BASED ACKNOWLEDGMENT FEEDBACK TECHNIQUES FOR WIRELESSCOMMUNICATIONS,” filed Jul. 4, 2019, each of which is assigned to theassignee hereof, and each of which is expressly incorporated byreference in its entirety herein.

BACKGROUND

The following relates generally to wireless communications, and morespecifically to group-based acknowledgment feedback techniques forwireless communications.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

Some wireless communications systems may support acknowledgment feedbackto indicate if a wireless device (e.g., a UE) successfully decodesdownlink messages (i.e., data transmissions) where the downlink messagedecoding is based on one or more detected downlink control messages(e.g., a downlink grant or downlink control information (DCI)). Indeployments supporting shared or unlicensed radio frequency spectrums(e.g., unlicensed NR), one or more downlink messages may not be receivedcorrectly (e.g., due to a hidden interfering node) and the wirelessdevice may not provide acknowledgment feedback based on all of thedownlink control messages. Further, in some cases a wireless device(e.g., a UE) may not be able to transmit acknowledgement feedback whenthe medium is occupied by another transmitter (e.g., when alisten-before-talk (LBT) procedure fails). Techniques to enhance systemperformance in cases where one or more transmissions may not be sent orreceived are thus desirable.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support group-based acknowledgment feedbacktechniques for wireless communications. In various aspects, group-basedfeedback may be provided in which a user equipment (UE) may transmitacknowledgment feedback (e.g., hybrid automatic repeat request (HARQ)feedback) for multiple downlink transmissions in a single uplinkcommunication. In some cases, two or more different groups of downlinktransmissions may each have an associated group-based acknowledgmentfeedback. In some cases, a base station may transmit downlink controlinformation to a UE that indicates one or more parameters that are usedto determine which downlink transmissions are to be reported in thegroup-based feedback. Based on the parameters in the downlink controlinformation, the UE may determine the feedback to be reported, and atiming for when to transmit the feedback to the base station.

In some cases, multiple instances of downlink control information may beused to determine the feedback to be reported by the UE, and varioustechniques discussed herein may be used when one or more parameters(e.g., a new acknowledgment feedback indicator (NFI) that indicates adownlink assignment indicator (DAI) counter is reset) change values inthe multiple instances of downlink control information. In some cases,various techniques discussed herein provide that one or more instancesof downlink control information may provide parameters for multipledifferent groups of downlink transmissions (e.g., NFI, DAI, or both, maybe provided for each of two groups of downlink transmissions). In someaspects of the present disclosure, downlink control information mayindicate that feedback is requested for multiple different groups ofdownlink transmissions, and feedback for the multiple groups may beappended together and transmitted to the base station.

In further aspects of the present disclosure, a downlink controlinformation format may be associated with group-based feedbacktransmissions and may include the one or more parameters for group-basedfeedback. In some cases, a fallback downlink control information formatmay also be used to indicate group-based feedback transmissions, andparameters associated with the group-based feedback may be determinedfrom other parameters in the fallback DCI that may be reused, may be setto predetermined values, or combinations thereof.

A method of wireless communications at a UE is described. The method mayinclude receiving a first downlink control information transmission froma base station that provides a first set of group-based acknowledgmentfeedback parameters associated with a first downlink transmission, wherethe first set of group-based acknowledgment feedback parameters includesa first new acknowledgment feedback indicator and a first feedbacktiming that indicates a first uplink transmission that is to include afirst group-based acknowledgment feedback, receiving a second downlinkcontrol information transmission from the base station that provides asecond set of group-based acknowledgment feedback parameters associatedwith a second downlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, and determining, based on which of the firstnew acknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time, the firstgroup-based acknowledgment feedback.

An apparatus for wireless communications at a UE is described. Theapparatus may include a processor, memory coupled with the processor,and instructions stored in the memory. The instructions may beexecutable by the processor to cause the apparatus to receive a firstdownlink control information transmission from a base station thatprovides a first set of group-based acknowledgment feedback parametersassociated with a first downlink transmission, where the first set ofgroup-based acknowledgment feedback parameters includes a first newacknowledgment feedback indicator and a first feedback timing thatindicates a first uplink transmission that is to include a firstgroup-based acknowledgment feedback, receive a second downlink controlinformation transmission from the base station that provides a secondset of group-based acknowledgment feedback parameters associated with asecond downlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, and determine, based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time, the firstgroup-based acknowledgment feedback.

Another apparatus for wireless communications at a UE is described. Theapparatus may include means for receiving a first downlink controlinformation transmission from a base station that provides a first setof group-based acknowledgment feedback parameters associated with afirst downlink transmission, where the first set of group-basedacknowledgment feedback parameters includes a first new acknowledgmentfeedback indicator and a first feedback timing that indicates a firstuplink transmission that is to include a first group-basedacknowledgment feedback, receiving a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters associated with a seconddownlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, and determining, based on which of the firstnew acknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time, the firstgroup-based acknowledgment feedback.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to receive a first downlink controlinformation transmission from a base station that provides a first setof group-based acknowledgment feedback parameters associated with afirst downlink transmission, where the first set of group-basedacknowledgment feedback parameters includes a first new acknowledgmentfeedback indicator and a first feedback timing that indicates a firstuplink transmission that is to include a first group-basedacknowledgment feedback, receive a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters associated with a seconddownlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, and determine, based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time, the firstgroup-based acknowledgment feedback.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining may includeoperations, features, means, or instructions for identifying that thesecond new acknowledgment feedback indicator being different than thefirst new acknowledgment feedback indicator for the first group-basedacknowledgment feedback corresponds to an error case, and discontinuinggenerating the first group-based acknowledgment feedback to betransmitted in the first uplink transmission. In some examples of themethod, apparatuses, and non-transitory computer-readable mediumdescribed herein, the determining further may include operations,features, means, or instructions for determining that the second newacknowledgment feedback indicator resets the first group-basedacknowledgment feedback for a subsequent second uplink transmission thatmay be to include group-based acknowledgment feedback.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first downlink controlinformation and the second downlink control information each furtherinclude a group indicator that indicates that both the first downlinktransmission and the second downlink transmission may be in a same groupof downlink transmissions.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for determining afirst acknowledgment (ACK)/negative-acknowledgment (NACK) to be reportedas feedback for the first downlink transmission and a second ACK/NACK tobe reported as feedback for the second downlink transmission, formattingthe first group-based acknowledgment feedback to include the firstACK/NACK and the second ACK/NACK based at least in part on the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator, and transmitting a latest subset of feedbackinformation associated with a latest received new acknowledgmentfeedback indicator.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first group-basedacknowledgment feedback is formatted based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for determining afirst ACK/NACK to be reported as feedback for the first downlinktransmission and a second ACK/NACK to be reported as feedback for thesecond downlink transmission, identifying that the second newacknowledgment feedback indicator being different than the first newacknowledgment feedback indicator for the first group-basedacknowledgment feedback may be interpreted as the new acknowledgmentfeedback indicator being untoggled from the first new acknowledgmentfeedback indicator, and formatting the first group-based acknowledgmentfeedback to include the first ACK/NACK and the second ACK/NACK based onthe first new acknowledgment feedback indicator or the second newacknowledgment feedback indicator.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, a downlink assignmentindicator field is not reset within anacknowledgment/negative-acknowledgment opportunity.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first group-basedacknowledgment feedback may be formatted relative to a prior group-basedacknowledgment feedback based on whether the first new acknowledgmentfeedback indicator may be different than a prior new acknowledgmentfeedback indicator associated with the prior group-based acknowledgmentfeedback, and a subsequent group-based acknowledgment feedback may beformatted relative to the first group-based acknowledgment feedbackbased on whether a subsequent new acknowledgment feedback indicator isdifferent than the second new acknowledgment feedback indicator.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first group-basedacknowledgment feedback may be formatted based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first group-basedacknowledgment feedback may be formatted based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received in a majority of sets of group-basedacknowledgment feedback parameters associated with the first group-basedacknowledgment feedback.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, to thebase station, the first group-based acknowledgment feedback in the firstuplink transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for identifyingthat the second new acknowledgment feedback indicator being differentthan the first new acknowledgment feedback indicator for the firstgroup-based acknowledgment feedback is interpreted as the newacknowledgment feedback indicator being toggled from the first newacknowledgment feedback indicator.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for identifyingthat the second new acknowledgment feedback indicator being differentthan the first new acknowledgment feedback indicator for the firstgroup-based acknowledgment feedback is interpreted as the newacknowledgment feedback indicator being toggled from the first newacknowledgment feedback indicator, and formatting a first subset offeedback information associated with the first new acknowledgmentfeedback indicator in the first group-based acknowledgment feedback anda second subset of feedback information associated with the second newacknowledgment feedback indicator in the first group-basedacknowledgment feedback.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for concatenating the firstsubset of feedback information and the second subset of feedbackinformation in the first group-based acknowledgment feedback. Someexamples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting only alatest subset of feedback information associated with a latest receivednew acknowledgment feedback indicator. In some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein, a downlink assignment indicator field is reset upon receipt of achanged new acknowledgment feedback indicator value, and where differentsubsets of feedback information are determined for each reset of thedownlink assignment indicator field. Some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein may further include operations, features, means, or instructionsfor identifying a first codebook entry associated with the first subsetof feedback information, identifying a second codebook entry associatedwith the second subset of feedback information, and transmitting, to thebase station, the first group-based acknowledgment feedback in the firstuplink transmission based on the first codebook entry and the secondcodebook entry.

A method of wireless communications at a base station is described. Themethod may include transmitting a first downlink control information toa user equipment (UE) that provides a first set of group-basedacknowledgment feedback parameters associated with a first downlinktransmission, where the first set of group-based acknowledgment feedbackparameters includes a first new acknowledgment feedback indicator and afirst feedback timing that indicates a first uplink transmission that isto include a first group-based acknowledgment feedback, transmitting asecond downlink control information to the UE that provides a second setof group-based acknowledgment feedback parameters associated with asecond downlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, transmitting the first downlink transmissionand the second downlink transmission to the UE, and receiving at leastthe first group-based acknowledgment feedback from the UE in the firstuplink transmission.

An apparatus for wireless communications at a base station is described.The apparatus may include a processor, memory coupled with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to transmit afirst downlink control information to a user equipment (UE) thatprovides a first set of group-based acknowledgment feedback parametersassociated with a first downlink transmission, where the first set ofgroup-based acknowledgment feedback parameters includes a first newacknowledgment feedback indicator and a first feedback timing thatindicates a first uplink transmission that is to include a firstgroup-based acknowledgment feedback, transmit a second downlink controlinformation to the UE that provides a second set of group-basedacknowledgment feedback parameters associated with a second downlinktransmission, where the second set of group-based acknowledgmentfeedback parameters includes a second new acknowledgment feedbackindicator that is different than the first new acknowledgment feedbackindicator, and a second feedback timing that indicates the first uplinktransmission is to include the first group-based acknowledgmentfeedback, transmit the first downlink transmission and the seconddownlink transmission to the UE, and receive at least the firstgroup-based acknowledgment feedback from the UE in the first uplinktransmission.

Another apparatus for wireless communications at a base station isdescribed. The apparatus may include means for transmitting a firstdownlink control information to a user equipment (UE) that provides afirst set of group-based acknowledgment feedback parameters associatedwith a first downlink transmission, where the first set of group-basedacknowledgment feedback parameters includes a first new acknowledgmentfeedback indicator and a first feedback timing that indicates a firstuplink transmission that is to include a first group-basedacknowledgment feedback, means for transmitting a second downlinkcontrol information to the UE that provides a second set of group-basedacknowledgment feedback parameters associated with a second downlinktransmission, where the second set of group-based acknowledgmentfeedback parameters includes a second new acknowledgment feedbackindicator that is different than the first new acknowledgment feedbackindicator, and a second feedback timing that indicates the first uplinktransmission is to include the first group-based acknowledgmentfeedback, means for transmitting the first downlink transmission and thesecond downlink transmission to the UE, and means for receiving at leastthe first group-based acknowledgment feedback from the UE in the firstuplink transmission.

A non-transitory computer-readable medium storing code for wirelesscommunications at a base station is described. The code may includeinstructions executable by a processor to transmit a first downlinkcontrol information to a user equipment (UE) that provides a first setof group-based acknowledgment feedback parameters associated with afirst downlink transmission, where the first set of group-basedacknowledgment feedback parameters includes a first new acknowledgmentfeedback indicator and a first feedback timing that indicates a firstuplink transmission that is to include a first group-basedacknowledgment feedback, transmit a second downlink control informationto the UE that provides a second set of group-based acknowledgmentfeedback parameters associated with a second downlink transmission,where the second set of group-based acknowledgment feedback parametersincludes a second new acknowledgment feedback indicator that isdifferent than the first new acknowledgment feedback indicator, and asecond feedback timing that indicates the first uplink transmission isto include the first group-based acknowledgment feedback, transmit thefirst downlink transmission and the second downlink transmission to theUE, and receive at least the first group-based acknowledgment feedbackfrom the UE in the first uplink transmission.

A method of wireless communications at a UE is described. The method mayinclude receiving a downlink control information transmission from abase station that provides a set of group-based acknowledgment feedbackparameters, where the set of group-based acknowledgment feedbackparameters includes a group indicator that identifies at least a firstgroup of downlink transmissions to be included in a first group-basedacknowledgement feedback transmission, a first downlink assignmentindicator that identifies one or more downlink transmissions of thefirst group of downlink transmissions, a second downlink assignmentindicator that identifies one or more downlink transmissions of a secondgroup of downlink transmissions, a first new acknowledgment feedbackindicator that identifies whether the first downlink assignmentindicator is reset, and a second new acknowledgment feedback indicatorassociated with the second group of downlink transmissions, receivingthe one or more downlink transmissions of the first group of downlinktransmissions, determining, based on the first downlink assignmentindicator and the first new acknowledgment feedback indicator, firstacknowledgment feedback associated with the first group of downlinktransmissions for inclusion with the first group-based acknowledgementfeedback transmission, updating the second group-based acknowledgementfeedback associated with the second group of downlink transmissionsbased on the determining, and transmitting the first group-basedacknowledgement feedback transmission to the base station.

An apparatus for wireless communications at a UE is described. Theapparatus may include a processor, memory coupled with the processor,and instructions stored in the memory. The instructions may beexecutable by the processor to cause the apparatus to receive a downlinkcontrol information transmission from a base station that provides a setof group-based acknowledgment feedback parameters, where the set ofgroup-based acknowledgment feedback parameters includes a groupindicator that identifies at least a first group of downlinktransmissions to be included in a first group-based acknowledgementfeedback transmission, a first downlink assignment indicator thatidentifies one or more downlink transmissions of the first group ofdownlink transmissions, a second downlink assignment indicator thatidentifies one or more downlink transmissions of a second group ofdownlink transmissions, a first new acknowledgment feedback indicatorthat identifies whether the first downlink assignment indicator isreset, and a second new acknowledgment feedback indicator associatedwith the second group of downlink transmissions, receive the one or moredownlink transmissions of the first group of downlink transmissions,determine, based on the first downlink assignment indicator and thefirst new acknowledgment feedback indicator, first acknowledgmentfeedback associated with the first group of downlink transmissions forinclusion with the first group-based acknowledgement feedbacktransmission, update the second group-based acknowledgement feedbackassociated with the second group of downlink transmissions based on thedetermining, and transmit the first group-based acknowledgement feedbacktransmission to the base station.

Another apparatus for wireless communications at a UE is described. Theapparatus may include means for receiving a downlink control informationtransmission from a base station that provides a set of group-basedacknowledgment feedback parameters, where the set of group-basedacknowledgment feedback parameters includes a group indicator thatidentifies at least a first group of downlink transmissions to beincluded in a first group-based acknowledgement feedback transmission, afirst downlink assignment indicator that identifies one or more downlinktransmissions of the first group of downlink transmissions, a seconddownlink assignment indicator that identifies one or more downlinktransmissions of a second group of downlink transmissions, a first newacknowledgment feedback indicator that identifies whether the firstdownlink assignment indicator is reset, and a second new acknowledgmentfeedback indicator associated with the second group of downlinktransmissions, receiving the one or more downlink transmissions of thefirst group of downlink transmissions, determining, based on the firstdownlink assignment indicator and the first new acknowledgment feedbackindicator, first acknowledgment feedback associated with the first groupof downlink transmissions for inclusion with the first group-basedacknowledgement feedback transmission, updating the second group-basedacknowledgement feedback associated with the second group of downlinktransmissions based on the determining, and transmitting the firstgroup-based acknowledgement feedback transmission to the base station.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to receive a downlink control informationtransmission from a base station that provides a set of group-basedacknowledgment feedback parameters, where the set of group-basedacknowledgment feedback parameters includes a group indicator thatidentifies at least a first group of downlink transmissions to beincluded in a first group-based acknowledgement feedback transmission, afirst downlink assignment indicator that identifies one or more downlinktransmissions of the first group of downlink transmissions, a seconddownlink assignment indicator that identifies one or more downlinktransmissions of a second group of downlink transmissions, a first newacknowledgment feedback indicator that identifies whether the firstdownlink assignment indicator is reset, and a second new acknowledgmentfeedback indicator associated with the second group of downlinktransmissions, receive the one or more downlink transmissions of thefirst group of downlink transmissions, determine, based on the firstdownlink assignment indicator and the first new acknowledgment feedbackindicator, first acknowledgment feedback associated with the first groupof downlink transmissions for inclusion with the first group-basedacknowledgement feedback transmission, update the second group-basedacknowledgement feedback associated with the second group of downlinktransmissions based on the determining, and transmit the firstgroup-based acknowledgement feedback transmission to the base station.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for determiningthat only the first group of downlink transmissions are to be includedin the first group-based acknowledgement feedback transmission, andignoring the second downlink assignment indicator and the second newacknowledgment feedback indicator associated with the second group ofdownlink transmissions.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, updating the secondgroup-based acknowledgement feedback is based on the second downlinkassignment indicator and the second new acknowledgment feedbackindicator for transmission of a second group-based acknowledgementfeedback transmission associated with the second group of downlinktransmissions.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for determiningthat a value of the second new acknowledgment feedback indicator isdifferent than a prior value of the second new acknowledgement feedbackindicator associated with the second group of downlink transmissionsfrom a prior downlink control information transmission from the basestation, and generating a negative acknowledgment for each downlinkassignment indicator associated with the second group of downlinktransmissions up to the second downlink assignment indicator, where aprevious downlink assignment indicator value for the second group ofdownlink transmissions prior to the second downlink assignment indicatoris discarded.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for determiningthat a value of the second new acknowledgment feedback indicator isunchanged from a prior value of the second new acknowledgement feedbackindicator associated with the second group of downlink transmissionsfrom a prior downlink control information transmission from the basestation, identifying one or more gaps between the second downlinkassignment indicator and a previous downlink assignment indicator valueassociated with the second group of downlink transmissions provided withthe prior downlink control information transmission from the basestation, and generating a negative acknowledgment for each downlinkassignment indicator associated with the one or more gaps.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining that boththe first group of downlink transmissions and the second group ofdownlink transmissions are to be included in the first group-basedacknowledgement feedback transmission, receiving one or more downlinktransmissions of the second group of downlink transmissions, anddetermining second acknowledgment feedback associated with the secondgroup of downlink transmissions for inclusion with the first group-basedacknowledgement feedback transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining may includeoperations, features, means, or instructions for determining that boththe first group of downlink transmissions and the second group ofdownlink transmissions are to be included in the first group-basedacknowledgement feedback transmission, and determining, based on thesecond group of downlink transmissions having a same new acknowledgmentfeedback indicator value as a prior downlink control informationtransmission that schedules a downlink transmission of the second groupof downlink transmissions, second acknowledgment feedback associatedwith the second group of downlink transmissions for inclusion with thefirst group-based acknowledgement feedback transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for identifying oneor more gaps between the second downlink assignment indicator and aprevious downlink assignment indicator value associated with the secondgroup of downlink transmissions provided with the prior downlink controlinformation transmission from the base station, and generating anegative acknowledgment for each downlink assignment indicatorassociated with the one or more gaps.

A method of wireless communications at a UE is described. The method mayinclude receiving a first downlink control information transmission froma base station that provides a first set of group-based acknowledgmentfeedback parameters, where the first set of group-based acknowledgmentfeedback parameters includes a first group indicator for a first groupof downlink transmissions, and a first feedback timing that indicates afirst uplink transmission is to include a first group-basedacknowledgment feedback associated with the first group of downlinktransmissions, receiving a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters, where the second set ofgroup-based acknowledgment feedback parameters includes a second groupindicator for a second group of downlink transmissions, and a secondfeedback timing that indicates the first uplink transmission is toinclude one or more of the first group-based acknowledgement feedback ora second group-based acknowledgment feedback associated with the secondgroup of downlink transmissions, and determining, based on the firstfeedback timing and the second feedback timing, that the first uplinktransmission is to include both the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback.

An apparatus for wireless communications at a UE is described. Theapparatus may include a processor, memory coupled with the processor,and instructions stored in the memory. The instructions may beexecutable by the processor to cause the apparatus to receive a firstdownlink control information transmission from a base station thatprovides a first set of group-based acknowledgment feedback parameters,where the first set of group-based acknowledgment feedback parametersincludes a first group indicator for a first group of downlinktransmissions, and a first feedback timing that indicates a first uplinktransmission is to include a first group-based acknowledgment feedbackassociated with the first group of downlink transmissions, receive asecond downlink control information transmission from the base stationthat provides a second set of group-based acknowledgment feedbackparameters, where the second set of group-based acknowledgment feedbackparameters includes a second group indicator for a second group ofdownlink transmissions, and a second feedback timing that indicates thefirst uplink transmission is to include one or more of the firstgroup-based acknowledgement feedback or a second group-basedacknowledgment feedback associated with the second group of downlinktransmissions, and determine, based on the first feedback timing and thesecond feedback timing, that the first uplink transmission is to includeboth the first group-based acknowledgement feedback and the secondgroup-based acknowledgment feedback.

Another apparatus for wireless communications at a UE is described. Theapparatus may include means for receiving a first downlink controlinformation transmission from a base station that provides a first setof group-based acknowledgment feedback parameters, where the first setof group-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions, receiving a second downlink controlinformation transmission from the base station that provides a secondset of group-based acknowledgment feedback parameters, where the secondset of group-based acknowledgment feedback parameters includes a secondgroup indicator for a second group of downlink transmissions, and asecond feedback timing that indicates the first uplink transmission isto include one or more of the first group-based acknowledgement feedbackor a second group-based acknowledgment feedback associated with thesecond group of downlink transmissions, and determining, based on thefirst feedback timing and the second feedback timing, that the firstuplink transmission is to include both the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to receive a first downlink controlinformation transmission from a base station that provides a first setof group-based acknowledgment feedback parameters, where the first setof group-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions, receive a second downlink controlinformation transmission from the base station that provides a secondset of group-based acknowledgment feedback parameters, where the secondset of group-based acknowledgment feedback parameters includes a secondgroup indicator for a second group of downlink transmissions, and asecond feedback timing that indicates the first uplink transmission isto include one or more of the first group-based acknowledgement feedbackor a second group-based acknowledgment feedback associated with thesecond group of downlink transmissions, and determine, based on thefirst feedback timing and the second feedback timing, that the firstuplink transmission is to include both the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first set of group-basedacknowledgment feedback parameters is the same as the second set ofgroup-based acknowledgment feedback parameters.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the one ormore downlink transmissions of the first group of downlink transmissionsand the second group of downlink transmissions, determining the firstgroup-based acknowledgment feedback associated with the first group ofdownlink transmissions and the second group-based acknowledgmentfeedback associated with the second group of downlink transmissions, andtransmitting the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback to the base station in thefirst uplink transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein none of the first set ofgroup-based acknowledgment feedback parameters or the second set ofgroup-based acknowledgment feedback parameters include an explicitindication that requests feedback of another group of downlinktransmissions.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for determiningthat both the first feedback timing the second feedback timing indicatea same uplink transmission slot.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining further mayinclude operations, features, means, or instructions for identifying afirst request field value in the first set of group-based acknowledgmentfeedback parameters that indicates a request for only the first group ofdownlink transmissions, and a second request field value in a subsequentdownlink control information transmission associated with the firstgroup of downlink transmissions that indicates a request for both thefirst group of downlink transmissions and the second group of downlinktransmissions, and determining that the first uplink transmission is toinclude both the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback based on the second requestfield value. In some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein, a latestreceived request field value is used to determine whether the firstuplink transmission includes both the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the UE is not expected toreceive different downlink control information transmissions thatschedule downlink transmissions of different downlink transmissiongroups and point to a same transmission time for the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein when an initial receivedrequest field value indicates that the first uplink transmission is toinclude both the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback, and a subsequent receivedrequest field value indicates that only one of the first group-basedacknowledgement feedback or the second group-based acknowledgmentfeedback is to be provided with the first uplink transmission, the UEdiscontinues group-based acknowledgment feedback determination for thefirst uplink transmission. In some examples of the method, apparatuses,and non-transitory computer-readable medium described herein the UEtransmits the first group-based acknowledgement feedback and the secondgroup-based acknowledgment feedback when at least one of the first setof group-based acknowledgment feedback parameters or the second set ofgroup-based acknowledgment feedback parameters indicates a request forboth the first group of downlink transmissions and the second group ofdownlink transmissions.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the one ormore downlink transmissions of the first group of downlink transmissionsand the second group of downlink transmissions, determining the firstgroup-based acknowledgment feedback associated with the first group ofdownlink transmissions and the second group-based acknowledgmentfeedback associated with the second group of downlink transmissions,formatting the first group-based acknowledgment feedback and the secondgroup-based acknowledgment feedback into a combined feedback report, andtransmitting the combined feedback report to the base station in thefirst uplink transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the formatting may includeoperations, features, means, or instructions for appending the secondgroup-based acknowledgment feedback to the first group-basedacknowledgment feedback based on a first group index of the firstgroup-based acknowledgment feedback having a lower index value than asecond group index of the second group-based acknowledgment feedback.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the formatting may includeoperations, features, means, or instructions for appending the secondgroup-based acknowledgment feedback to the first group-basedacknowledgment feedback based on a request for the second group-basedacknowledgment feedback being received in downlink control informationassociated with the first group of transmissions.

A method of wireless communications at a UE is described. The method mayinclude receiving, from a base station, configuration information forgroup-based acknowledgment feedback for one or more groups of downlinktransmissions to the UE, where one or more parameters associated withthe group-based acknowledgment feedback are indicated in a first set offields of a first downlink control information format, and are absentfrom a second set of fields of a second downlink control informationformat that is different than the first set of fields, where the firstset of fields includes a first subset of information fields that are inaddition to the second set of fields, receiving a downlink controlinformation transmission from the base station having the seconddownlink control information format, determining, based on apredetermined value for each field of the first subset of informationfields, first acknowledgment feedback associated with at least a firstgroup of downlink transmissions, and transmitting the firstacknowledgment feedback to the base station.

An apparatus for wireless communications at a UE is described. Theapparatus may include a processor, memory coupled with the processor,and instructions stored in the memory. The instructions may beexecutable by the processor to cause the apparatus to receive, from abase station, configuration information for group-based acknowledgmentfeedback for one or more groups of downlink transmissions to the UE,where one or more parameters associated with the group-basedacknowledgment feedback are indicated in a first set of fields of afirst downlink control information format, and are absent from a secondset of fields of a second downlink control information format that isdifferent than the first set of fields, where the first set of fieldsincludes a first subset of information fields that are in addition tothe second set of fields, receive a downlink control informationtransmission from the base station having the second downlink controlinformation format, determine, based on using a predetermined value foreach field of the first subset of information fields, firstacknowledgment feedback associated with at least a first group ofdownlink transmissions, and transmit the first acknowledgment feedbackto the base station.

Another apparatus for wireless communications at a UE is described. Theapparatus may include means for receiving, from a base station,configuration information for group-based acknowledgment feedback forone or more groups of downlink transmissions to the UE, where one ormore parameters associated with the group-based acknowledgment feedbackare indicated in a first set of fields of a first downlink controlinformation format, and are absent from a second set of fields of asecond downlink control information format that is different than thefirst set of fields, where the first set of fields includes a firstsubset of information fields that are in addition to the second set offields, receiving a downlink control information transmission from thebase station having the second downlink control information format,determining, based on using a predetermined value for each field of thefirst subset of information fields, first acknowledgment feedbackassociated with at least a first group of downlink transmissions, andtransmitting the first acknowledgment feedback to the base station.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to receive, from a base station, configurationinformation for group-based acknowledgment feedback for one or moregroups of downlink transmissions to the UE, where one or more parametersassociated with the group-based acknowledgment feedback are indicated ina first set of fields of a first downlink control information format,and are absent from a second set of fields of a second downlink controlinformation format that is different than the first set of fields, wherethe first set of fields includes a first subset of information fieldsthat are in addition to the second set of fields, receive a downlinkcontrol information transmission from the base station having the seconddownlink control information format, determine, based on using apredetermined value for each field of the first subset of informationfields, first acknowledgment feedback associated with at least a firstgroup of downlink transmissions, and transmit the first acknowledgmentfeedback to the base station.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, from thebase station, an indication to enable the group-based acknowledgmentfeedback, and where the second set of fields of the second downlinkcontrol information format is interpreted differently based on whetherthe group-based acknowledgment feedback is enabled or disabled at theUE. In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the second downlink controlinformation format is a fallback downlink control information format.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first subset ofinformation fields include one or more of a group indicator field, a newacknowledgment feedback indicator field, or a request field thatindicates acknowledgment feedback is requested for one or more ofmultiple different groups of downlink transmissions.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the predetermined value forthe group indicator field corresponds to a downlink transmission groupassociated with the downlink control information transmission, thepredetermined value for the new acknowledgment feedback indicator fieldcorresponds to a prior value of the new acknowledgment feedbackindicator field, the predetermined value for the request fieldcorresponds to a value that indicates acknowledgment feedback may be notrequested for another group of downlink transmissions.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the determining may includeoperations, features, means, or instructions for formatting the firstacknowledgment feedback for one or more downlink transmissionsassociated with the first downlink control information format separatelyfrom second acknowledgment feedback associated with a different downlinkcontrol information having the second downlink control informationformat. In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, a downlink assignmentindicator field of the second downlink control information format may beapplied separately when determining the second acknowledgment feedback.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first acknowledgmentfeedback includes feedback information only for downlink transmissionsassociated with only the first downlink control information format oronly the second downlink control information format.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first acknowledgmentfeedback includes feedback information for downlink transmissionsassociated with both the first downlink control information format andthe second downlink control information format.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first acknowledgmentfeedback includes feedback information based on one or more of a firstcodebook for downlink transmissions associated with the second downlinkcontrol information format, a second codebook for downlink transmissionsassociated with the second downlink control information format having afirst group identification, or a third codebook for downlinktransmissions associated with the second downlink control informationformat having a second group identification.

A method of wireless communications at a UE is described. The method mayinclude receiving a first downlink control information transmission froma base station that is associated with a first group-based downlinktransmission and a first acknowledgment feedback occasion, receiving asecond downlink control information transmission, subsequent to thefirst downlink control information transmission, that is associated witha second non-group-based downlink transmission and a secondacknowledgment feedback occasion, transmitting non-group-basedacknowledgment feedback associated with the second non-group-baseddownlink transmission in the second acknowledgment feedback occasion,receiving a third downlink control information transmission, subsequentto the second downlink control information transmission, that isassociated with a third group-based downlink transmission and a thirdacknowledgment feedback occasion, and transmitting group-basedacknowledgment feedback associated with one or more or the firstgroup-based downlink transmission or the third group-based downlinktransmission in the third acknowledgment feedback occasion.

An apparatus for wireless communications at a UE is described. Theapparatus may include a processor, memory coupled with the processor,and instructions stored in the memory. The instructions may beexecutable by the processor to cause the apparatus to receive a firstdownlink control information transmission from a base station that isassociated with a first group-based downlink transmission and a firstacknowledgment feedback occasion, receive a second downlink controlinformation transmission, subsequent to the first downlink controlinformation transmission, that is associated with a secondnon-group-based downlink transmission and a second acknowledgmentfeedback occasion, transmit non-group-based acknowledgment feedbackassociated with the second non-group-based downlink transmission in thesecond acknowledgment feedback occasion, receive a third downlinkcontrol information transmission, subsequent to the second downlinkcontrol information transmission, that is associated with a thirdgroup-based downlink transmission and a third acknowledgment feedbackoccasion, and transmit group-based acknowledgment feedback associatedwith one or more or the first group-based downlink transmission or thethird group-based downlink transmission in the third acknowledgmentfeedback occasion.

Another apparatus for wireless communications at a UE is described. Theapparatus may include means for receiving a first downlink controlinformation transmission from a base station that is associated with afirst group-based downlink transmission and a first acknowledgmentfeedback occasion, receiving a second downlink control informationtransmission, subsequent to the first downlink control informationtransmission, that is associated with a second non-group-based downlinktransmission and a second acknowledgment feedback occasion, transmittingnon-group-based acknowledgment feedback associated with the secondnon-group-based downlink transmission in the second acknowledgmentfeedback occasion, receiving a third downlink control informationtransmission, subsequent to the second downlink control informationtransmission, that is associated with a third group-based downlinktransmission and a third acknowledgment feedback occasion, andtransmitting group-based acknowledgment feedback associated with one ormore or the first group-based downlink transmission or the thirdgroup-based downlink transmission in the third acknowledgment feedbackoccasion.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to receive a first downlink controlinformation transmission from a base station that is associated with afirst group-based downlink transmission and a first acknowledgmentfeedback occasion, receive a second downlink control informationtransmission, subsequent to the first downlink control informationtransmission, that is associated with a second non-group-based downlinktransmission and a second acknowledgment feedback occasion, transmitnon-group-based acknowledgment feedback associated with the secondnon-group-based downlink transmission in the second acknowledgmentfeedback occasion, receive a third downlink control informationtransmission, subsequent to the second downlink control informationtransmission, that is associated with a third group-based downlinktransmission and a third acknowledgment feedback occasion, and transmitgroup-based acknowledgment feedback associated with one or more or thefirst group-based downlink transmission or the third group-baseddownlink transmission in the third acknowledgment feedback occasion.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein acknowledgment feedbackassociated with the second acknowledgment feedback occasion may be notretransmitted in the third acknowledgment feedback occasion.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, a new acknowledgment feedbackindicator (NFI) may be assumed to be toggled between the firstacknowledgment feedback occasion and the third acknowledgment feedbackoccasion.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining that a newacknowledgment feedback indicator (NFI) may be toggled between the firstacknowledgment feedback occasion and the third acknowledgment feedbackoccasion based on a difference in a first NFI value provided in thefirst downlink control information and a second NFI value provided inthe third downlink control information.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports group-based acknowledgment feedback techniques forwireless communications in accordance with aspects of the presentdisclosure.

FIG. 2 illustrates an example of a portion of a wireless communicationssystem that supports group-based acknowledgment feedback techniques forwireless communications in accordance with aspects of the presentdisclosure.

FIGS. 3 through 8 illustrate examples of feedback timelines that supportgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure.

FIGS. 9 and 10 show block diagrams of devices that support group-basedacknowledgment feedback techniques for wireless communications inaccordance with aspects of the present disclosure.

FIG. 11 shows a block diagram of a communications manager that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure.

FIG. 12 shows a diagram of a system including a device that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure.

FIGS. 13 and 14 show block diagrams of devices that support group-basedacknowledgment feedback techniques for wireless communications inaccordance with aspects of the present disclosure.

FIG. 15 shows a block diagram of a communications manager that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure.

FIG. 16 shows a diagram of a system including a device that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure.

FIGS. 17 through 24 show flowcharts illustrating methods that supportgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

The described aspects of the disclosure relate to improved methods,systems, devices, or apparatuses that facilitate feedback fortransmissions or retransmissions, such as hybrid automatic repeatrequest (HARQ) acknowledgment/negative-acknowledgment (ACK/NACK)feedback reports. In some examples, the techniques described hereinenable efficient group-based feedback reporting, in which feedback for anumber of different downlink transmissions may be provided by a userequipment (UE) to a base station in a wireless communications system. Insome cases, two or more different groups of downlink transmissions mayeach have an associated group-based acknowledgment feedback. In somecases, a base station may transmit downlink control information (DCI) toa UE that indicates one or more parameters that are used to determinewhich downlink transmissions are to be reported in the group-basedfeedback. Based on the parameters in the DCI, the UE may determine thefeedback to be reported, and a timing for when to transmit the feedbackto the base station.

In some cases, multiple instances of DCI may be used to determine thefeedback to be reported by the UE, and techniques discussed hereinprovide UE actions when one or more parameters (e.g., a newacknowledgment feedback indicator (NFI) that indicates a downlinkassignment indicator (DAI) counter is reset) change values in themultiple instances of DCI that are each associated with a samegroup-based feedback report. In some cases, if two or more DCIs indicatea same uplink slot for a group-based acknowledgment feedbacktransmission, and also have different NFI values, the UE may treat it asan error case and the group-based acknowledgment feedback transmissionmay not be transmitted. In other cases, the UE may consider the NFI notto be toggled in the DCIs, and may use the NFI provided in an initialDCI, a last DCI, or a majority rule among NFI values on received DCIs.In other cases, multiple feedback codebooks may be determined for thegroup of downlink transmission for each instance that the NFI istoggled, and one or more of the multiple feedback codebooks transmittedas the group-based acknowledgment feedback.

In some cases, various techniques discussed herein provide that one ormore instances of DCI may provide parameters for multiple differentgroups of downlink transmissions (e.g., NFI, DAI, or both, may beprovided for each of two groups of downlink transmissions). In somecases, one or more DCI transmissions may include a first DAI value for afirst downlink transmission group associated with the DCI (i.e., the DCIincludes scheduling information for a first downlink transmission of thefirst downlink transmission group), and may include a second DAI valuefor a second downlink transmission group that does not have any downlinktransmissions scheduled by the DCI. In some cases, one or more DCIs mayalso include NFI values associated with both the first and seconddownlink transmission groups. In such cases, a UE may update the DAI andNFI of the second group and, if feedback is requested for the secondgroup, generate a feedback codebook based on the DAI and NFI andtransmit the feedback to the base station. In some cases, DCIs mayinclude a DAI for the second group but not an NFI for the second group,in which cases the UE may assume that the NFI for the second group isequal to a previous NFI value for the second group.

In some aspects of the present disclosure, downlink control informationmay indicate that feedback is requested for multiple different groups ofdownlink transmissions, and feedback for the multiple groups may beappended together and transmitted to the base station. In some cases, arequest bit may be included with DCI transmissions, and may indicatewhether feedback is requested for only the downlink transmission groupassociated with the DCI, or whether feedback is also requested for oneor more other downlink transmission groups. In other cases, a requestbit may not be included with DCI transmissions, and the UE may determinethat feedback for multiple groups is requested based on multiple DCIsthat are associated with different downlink transmission groups thateach indicate a same uplink transmission time (e.g., a same uplink slot)for the acknowledgement feedback transmission. In some cases, when arequest bit is included with DCI, a UE may determine that a value of therequest bit changes in different DCI transmissions. In such cases, theUE may use the value of the indicator of the latest DCI, or maydetermine that an error case exists and not transmit the feedbacktransmission. In some cases, if at least one DCI includes the requestbit that indicates feedback for multiple groups is requested, the UE maytransmit feedback for the multiple groups. In some cases, the UE may notbe expected to receive DCIs scheduling downlink transmissions thatbelong to different downlink transmission groups and point to a sameuplink transmission time for transmission of the feedback reports, andthus base stations may be prohibited from transmitting such DCIs. Incases where feedback reports for two or more downlink transmissiongroups are transmitted, the UE may append codebooks for each grouptogether for transmission, such as based on a group index of thedownlink transmission groups or based on which group is associated withthe DCI that requests the feedback (e.g., if the DCI is for a firstgroup and also requests feedback for a second group, the feedback forthe first group is determined and the feedback for the second group isappended thereto for transmission).

In further aspects of the present disclosure, a DCI format may beassociated with group-based feedback transmissions and may include theone or more parameters for group-based feedback (e.g., DCI format 1_1).In some cases, a fallback DCI format (e.g., DCI format 1_0) may also beused to indicate group-based feedback transmissions, and parametersassociated with the group-based feedback may be determined from otherparameters in the fallback DCI that may be reused, may be set topredetermined values, or combinations thereof. In some cases, ifgroup-based acknowledgment feedback is enabled at a UE (e.g., throughradio resource control (RRC) signaling), and the UE receives thefallback DCI, one or more existing fields of the fallback DCI may beinterpreted to provide group-based feedback parameters (e.g., based on aset of predefined rules). Additionally or alternatively, the UE mayassume a fixed value for one or more group-based feedback parameters. Inother cases, feedback reports corresponding to downlink transmissionsscheduled by fallback DCIs may be constructed separately from feedbackreports corresponding to downlink transmissions scheduled bynon-fallback DCIs.

In some cases, a first set of group-based DCIs may be associated with afirst feedback opportunity, a second set of fallback DCIs may beassociated with a second feedback opportunity, and a third set ofgroup-based DCIs may be associated with a third feedback opportunity. Insuch cases, the second feedback opportunity may include feedback onlyfor the non-group-based transmissions associated with the second set offallback DCIs, and the third feedback opportunity may include feedbackfor any of the transmissions associated with the first set ofgroup-based DCIs or the third set of group-based DCIs (but not fortransmissions associated with the second set of fallback DCIs). In somecases, the UE may assume an NFI associated with the third set ofgroup-based DCIs is toggled relative to the NFI of the first set ofgroup-based DCIs. In other cases, a difference in a value of one or moreNFIs of the first set of group-based DCIs and one or more NFIs of thethird set of group-based DCIs may be used to determine if the NFI istoggled.

In some cases, techniques as discussed herein may be used in a wirelesscommunications system that supports communications in an unlicensedspectrum (e.g., a shared radio frequency spectrum band), licensedspectrum, or a combination of licensed and unlicensed spectrums. In suchsystems, one or more transmissions may not be successfully received dueto interference from a hidden node, or may not be transmitted due to alisten-before-talk (LBT) procedure failure. Accordingly, theacknowledgment feedback may not include feedback for one or more missedfeedback process IDs (e.g., due to interference, LBT failure, etc.).Group-based feedback reports may be used in such cases, which allow theUE to transmit feedback for all of the feedback processes that areconfigured at the UE. Thus, techniques such as discussed herein mayallow for efficient acknowledgment feedback that may help reduce latencyand enhance overall system throughput in a wireless communicationsystem.

Aspects of the disclosure are initially described in the context of awireless communications system. Additional aspects of the disclosure arethen described with respect to several techniques for group-basedacknowledgment feedback. Aspects of the disclosure are furtherillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that relate to group-basedacknowledgment feedback techniques for wireless communications.

FIG. 1 illustrates an example of a wireless communications system 100that supports group-based acknowledgment feedback techniques forwireless communications in accordance with aspects of the presentdisclosure. The wireless communications system 100 includes basestations 105, UEs 115, and a core network 130. In some examples, thewireless communications system 100 may be a Long Term Evolution (LTE)network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a NewRadio (NR) network. In some cases, wireless communications system 100may support enhanced broadband communications, ultra-reliable (e.g.,mission critical) communications, low latency communications, orcommunications with low-cost and low-complexity devices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB orgiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up a portion of the geographic coverage area 110,and each sector may be associated with a cell. For example, each basestation 105 may provide communication coverage for a macro cell, a smallcell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for UEs 115 include entering a powersaving “deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 134 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105) or indirectly (e.g.,via core network 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features. However, the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter range (e.g., less than 100 km) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

Wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that may be capable of toleratinginterference from other users.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a carrieraggregation configuration in conjunction with component carriersoperating in a licensed band (e.g., LAA). Operations in unlicensedspectrum may include downlink transmissions, uplink transmissions,peer-to-peer transmissions, or a combination of these. Duplexing inunlicensed spectrum may be based on frequency division duplexing (FDD),time division duplexing (TDD), or a combination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving device is equipped with one or moreantennas. MIMO communications may employ multipath signal propagation toincrease the spectral efficiency by transmitting or receiving multiplesignals via different spatial layers, which may be referred to asspatial multiplexing. The multiple signals may, for example, betransmitted by the transmitting device via different antennas ordifferent combinations of antennas. Likewise, the multiple signals maybe received by the receiving device via different antennas or differentcombinations of antennas. Each of the multiple signals may be referredto as a separate spatial stream, and may carry bits associated with thesame data stream (e.g., the same codeword) or different data streams.Different spatial layers may be associated with different antenna portsused for channel measurement and reporting. MIMO techniques includesingle-user MIMO (SU-MIMO) where multiple spatial layers are transmittedto the same receiving device, and multiple-user MIMO (MU-MIMO) wheremultiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer mayperform packet segmentation and reassembly to communicate over logicalchannels. A Medium Access Control (MAC) layer may perform priorityhandling and multiplexing of logical channels into transport channels.The MAC layer may also use hybrid automatic repeat request (HARQ) toprovide retransmission at the MAC layer to improve link efficiency. Inthe control plane, the Radio Resource Control (RRC) protocol layer mayprovide establishment, configuration, and maintenance of an RRCconnection between a UE 115 and a base station 105 or core network 130supporting radio bearers for user plane data. At the Physical layer,transport channels may be mapped to physical channels.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period ofT_(s)=1/30,720,000 seconds. Time intervals of a communications resourcemay be organized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communications system 100, andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communications system100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs).

In some wireless communications systems, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a symbol of a mini-slot or a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communications systems may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)), and may be positionedaccording to a channel raster for discovery by UEs 115. Carriers may bedownlink or uplink (e.g., in an FDD mode), or be configured to carrydownlink and uplink communications (e.g., in a TDD mode). In someexamples, signal waveforms transmitted over a carrier may be made up ofmultiple sub-carriers (e.g., using multi-carrier modulation (MCM)techniques such as orthogonal frequency division multiplexing (OFDM) ordiscrete Fourier transform spread OFDM (DFT-S-OFDM)).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR).For example, communications over a carrier may be organized according toTTIs or slots, each of which may include user data as well as controlinformation or signaling to support decoding the user data. A carriermay also include dedicated acquisition signaling (e.g., synchronizationsignals or system information, etc.) and control signaling thatcoordinates operation for the carrier. In some examples (e.g., in acarrier aggregation configuration), a carrier may also have acquisitionsignaling or control signaling that coordinates operations for othercarriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may consist ofone symbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communications system 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth, or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communications system 100 mayinclude base stations 105 and/or UEs 115 that support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth.

Wireless communications system 100 may support communication with a UE115 on multiple cells or carriers, a feature which may be referred to ascarrier aggregation or multi-carrier operation. A UE 115 may beconfigured with multiple downlink component carriers and one or moreuplink component carriers according to a carrier aggregationconfiguration. Carrier aggregation may be used with both FDD and TDDcomponent carriers.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback such as discussed herein is one technique of increasingthe likelihood that data is received correctly over a communication link125. HARQ may include a combination of error detection (e.g., using acyclic redundancy check (CRC)), forward error correction (FEC), andretransmission (e.g., automatic repeat request (ARQ)). HARQ may improvethroughput at the MAC layer in poor radio conditions (e.g.,signal-to-noise conditions). In some cases, a wireless device maysupport group-based acknowledgment feedback in which HARQ feedback forone or more groups of downlink transmissions may be transmitted from aUE 115 to a base station 105 in a single uplink communication. Varioustechniques described herein enable efficient group-based acknowledgmentfeedback reporting, in which feedback for a number of different downlinktransmissions may be provided by a UE 115 to a base station 105.

FIG. 2 illustrates an example of a wireless communications system 200that supports group-based acknowledgment feedback techniques forwireless communications in accordance with aspects of the presentdisclosure. In some examples, wireless communications system 200 mayimplement aspects of wireless communications system 100. Wirelesscommunications system 200 may include a base station 105-a and a UE115-a, which may be examples of corresponding base stations 105 and UEs115 as described with reference to FIG. 1.

As described herein, base station 105-a and UE 115-a may employ HARQfeedback techniques to indicate whether data has been received correctlyat UE 115-a. For example, base station 105-a may transmit one or moredownlink messages to UE 115-a on resources of a carrier 205.Accordingly, UE 115-a may transmit an indication of whether the one ormore downlink messages were received and decoded correctly on resourcesof a carrier 210. In some cases, carriers 205 and 210 may be the samecarrier. In some cases, carriers 205 and 210 may be component carriers(CCs), and a number of different CCs may be used for communicationsbetween the UE 115-a and the base station 105-a. In some cases, carriers205 and 210 may use licensed spectrum, shared or unlicensed spectrum, orcombinations thereof. When using unlicensed or shared spectrum, the UE115-a and base station 105-a may use a contention-based access technique(e.g., an LBT procedure) to determine if a channel is available prior toinitiating transmissions.

In this example, base station 105-a may transmit a group-based feedbackDCI 215 on carrier 205, and UE 115-a responds with feedback report 220on carrier 210. The group-based feedback DCI 215 may be included in adownlink or uplink grant (e.g., downlink message such as a physicaldownlink control channel (PDCCH) transmission), or UE 115-a may beexplicitly triggered to transmit feedback report 220 (e.g., in aseparate DCI message). When group-based feedback DCI 215 is present, UE115-a may be indicated, by base station 105-a, to provide the feedbackreport 220 based on one or more group-based feedback parameters. Forexample, the base station 105-a may configure the UE 115-a forgroup-based feedback, and the UE 115-a may prepare and transmit feedbackreport 220 based on the group-based feedback configuration.

In some cases, the wireless communications system 200 may operate in anNR system, which may allow for two modes of transmission of a HARQ-ACKcodebook, which may include a semi-static (e.g., Type 1) mode, and adynamic (e.g., Type 2) mode. A dynamic feedback mode may allow forgrouping of multiple downlink transmissions (e.g., physical downlinkshared channel (PDSCH) grouping for one or more PDSCH groups) bysignaling a feedback parameters that provides a group identification(e.g., a group index may be provided in a DCI scheduling a PDSCHtransmission). In some cases, such feedback parameters may include anindication of an uplink transmission timing (e.g., a value of K1 thatindicates a number of slots between a downlink transmission and a slotthat is to include the feedback report 220). In some cases, anon-numerical value of uplink transmission timing (e.g., a non-numericK1) that may indicate that the feedback report 220 is to be transmittedresponsive to a trigger event (e.g., a trigger from the base station105-a). In cases of numeric or non-numeric uplink transmission timing, anumber of feedback bits (e.g., HARQ ACK/NACK indications for downlinktransport blocks (TBs)/code block groups (CBGs)) can change betweensuccessive requests for acknowledgment feedback for the same downlinktransmission group. In some cases, the feedback report 220 may carryfeedback in a same uplink transmission (e.g., a same physical uplinkcontrol channel (PUCCH) transmission) for each of a number of differentdownlink transmissions in a downlink transmission group. Further, insome cases, a single group-based feedback DCI 215 may requestacknowledgment feedback for one or more downlink transmission groups ina same feedback report 220.

In some cases, the group-based feedback DCI 215 may include anindication of one or more downlink assignment index (DAI) that mayprovide a counter of downlink assignments (e.g., TB or CBG downlinktransmissions) that are to be reported in a feedback report 220. In somecases, the DAIs may include a counter DAI (cDAI) that may indicate anaccumulated number of downlink transmissions within each downlinktransmission group. In some cases, the cDAI may count up using a modulofour operation (e.g., the cDAI value may be provided using two bits, inwhich the UE 115-a and base station 105-a may determine the cDAI basedon whether the bits have rolled-over due to the modulo operation). Insome cases, the DAIs may also include a total DAI (tDAI), that mayindicate a total number of DAIs across multiple component carriers ordownlink transmission groups, which may also use a modulo operation asdiscussed with the cDAI. The tDAI may thus provide an indication ofwhether the UE 115-a may have missed a DCI for a carrier. In some cases,the tDAI may be provided only for the scheduled downlink transmissiongroup. In other cases, the tDAI may be provided for each downlinktransmission group irrespective of whether the DCI has schedulinginformation for a group. In some cases, the feedback parameters may alsoinclude a new acknowledgment feedback indicator (NFI) for each downlinktransmission group which may operate as a toggle bit that, when toggled,indicates the DAI for the downlink transmission group is to be reset. Insome cases, the UE 115-a may provide a capability report to the basestation 105-a that indicates a capability of the UE to supportgroup-based acknowledgment feedback.

When providing the feedback report 220, in some cases, the UE 115-a maydetermine a feedback codebook that is reported to the base station 105-ato indicate ACK/NACK for each associated downlink transmission (e.g.,for each scheduled TB/CBG) that is to be reported at the associateduplink transmission time. In some cases, the codebook may be determinedbased on PDCCH monitoring occasions (e.g., based on configuration ofdifferent search space (SS) sets in different serving cells, as a unionof PDCCH monitoring occasions across active downlink bandwidth parts(BWPs) of configured serving cells, ordered in ascending order of starttime of the SS set associated with a PDCCH monitoring occasion). If twoSS sets (of the same or different serving cells) have the same starttime, it is counted as one PDCCH monitoring occasion. The feedbackcodebook may also be determined based on the DAIs that are received viaDCI transmissions where, if a DCI is not missed, an ACK/NACK bitcorresponding to the received PDSCH is placed in the codebook in thesame order as cDAI. If a DCI is missed, a NACK is placed in the codebookin the same order as the missed cDAI. In some cases, the UE 115-a maydetermine if a DCI is missed by comparing consecutive cDAI values (e.g.,consecutive cDAI values of 0, 1, 3 means that a DCI with cDAI value of 2is missed). In cases where tDAI is transmitted, the UE 115-a maydetermine if a DCI is missed by comparing tDAI with cDAI of all DCIs inthe same PDCCH monitoring occasion (e.g., for two serving cells in agiven PDCCH monitoring occasion, if only one DCI with (cDAI,tDAI)=(1,2)is received, this means that the second DCI is missed). As indicated,the UE 115-a may insert a NACK in the feedback report 220 for eachmissed DCI according to an order of the DAIs.

As will be discussed in more detail with reference to FIGS. 3 through 8,in various examples different group-based feedback parameters may beprovided in one or more group-based feedback DCIs 215. The feedbackreport 220 may include group-based acknowledgment feedback in accordancewith various discussed techniques for one or more groups of downlinktransmissions based on the group-based feedback parameters. In caseswhere feedback is provided for two or more groups of downlinktransmissions, feedback information may be multiplexed together in asingle feedback report 220 in an uplink communication from the UE 115-ato the base station 105-a.

FIG. 3 illustrates an example of a feedback timeline 300 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Insome examples, feedback timeline 300 may implement aspects of wirelesscommunications system 100 or 200. In this example, a number oftransmission slots 305 are illustrated, including a first transmissionslot 305-a through a tenth transmission slot 305-j. In some cases,transmissions using transmission slots 305 may use licensed spectrum,unlicensed spectrum, or combinations thereof.

In this example, a first DCI 310 may be transmitted in the first slot305-a, that may include downlink scheduling information for anassociated PDSCH transmission 315 in the first slot 305-a. In thisexample, the first DCI 310 may include group-based feedback parameters,including a timing value, K1, provided in a PDSCH-to-HARQ_feedbacktiming indicator field that indicates a number of slots between theassociated PDSCH and when the acknowledgment feedback is to betransmitted. In this case K1 indicates that the associatedacknowledgment feedback is to be provided three slots (e.g., K1=3) afterthe first slot 305-a (e.g., in fourth slot 305-d). In this example thefirst DCI 310 may also indicate a DAI value of one (DAI=1) which maycorrespond to a cDAI value that indicates the DAI is for an initialacknowledgment feedback indicator to be included in an acknowledgmentcodebook. In some cases, the first DCI 310 may also include a tDAI value(e.g., in cases where downlink carrier aggregation is enabled), which isnot illustrated in this example for purposes of simplicity. In thisexample the first DCI 310 also indicates a group index (G) thatidentifies an associated downlink transmission group of the first DCI310 and associated PDSCH transmission 315. The first DCI 310 alsoincludes a request indicator (R) that indicates whether a feedbackreport is requested for only the same group that is associated with theDCI (i.e., group 0) or a feedback report is also requested for anothergroup (e.g., R=0 indicates feedback for only the same group isrequested; and R=1 indicates feedback for the other group is alsorequested). The first DCI 310, in this example, also includes an NFIthat is a single-bit indicator associated with the group of the firstDCI 310 that, if toggled, means that the corresponding group is reset(i.e., DAI is reset, which implies that the previous HARQ-ACK feedbackis correctly received by the base station).

In the example of FIG. 3, a second DCI 320 may schedule a second PDSCHtransmission 325 in second slot 305-b. In this example, the second DCI320 includes group-based feedback parameters of K1=2 (i.e., that theassociated acknowledgment feedback is to be provided in the fourth slot305-d), DAI=2 (i.e., the next consecutive DAI count indicating that oneor more DAIs have not been missed), G=0 (i.e., for the same group as thefirst DCI 310 and first PDSCH transmission 315), R=0 (i.e., thatfeedback for another group is not requested), and NFI=0 (i.e., that theDAI has not been reset based on not being toggled from the prior DCI).In this example, a third slot 305-c may not include any transmissionsassociated with the particular UE, and the fourth slot 305-d may includeresources for an uplink transmission, namely a PUCCH transmission 330,for reporting of the group-based acknowledgment feedback.

As discussed herein, a UE receiving downlink transmissions of thedownlink transmission group may format a feedback codebook 335 thatincludes bits associated with each DAI indicated in the received DAIfields. Thus, in this example, feedback codebook 335 includes anACK/NACK bit associated with DAI=1 of the first slot 305-a, and a secondACK/NACK bit associated with DAI=2 of the second slot 305-b. In thisexample, the PUCCH transmission 330 may not be successfully received atthe base station. For example, interference or low channel qualitybetween the UE and base station may have prevented the base station fromsuccessfully receiving and decoding the PUCCH transmission 330. In somecases, the UE and base station may operate in shared or unlicensedspectrum, and the PUCCH transmission 330 may not be received due to anunsuccessful contention-based channel access procedure (e.g., a LBTprocedure failure) that did not allow the UE to send PUCCH transmission330.

In this example, the base station may determine that the PUCCHtransmission 330 is not successfully received, and may thus maintain DCIparameters for group-based acknowledgment feedback in order to obtainthe feedback associated with the first slot 305-a and the second slot305-b. In this example, in fifth slot 305-e, the base station maytransmit a third DCI 340 for an associated third PDSCH transmission 345.In this example, the third DCI 340 includes group-based feedbackparameters of K1=2 (i.e., that the associated acknowledgment feedback isto be provided in the seventh slot 305-g), DAI=3 (i.e., the nextconsecutive DAI count indicating that one or more DAIs have not beenmissed), G=0 (i.e., for the same group as the first DCI 310 and firstPDSCH transmission 315), R=0 (i.e., that feedback for another group isnot requested), and NFI=0 (i.e., that the DAI has not been reset basedon not being toggled from the prior DCI). In this example a sixth slot305-f may not include any transmissions associated with the particularUE, and the seventh slot 305-g may include resources for a second PUCCHtransmission 350, for reporting of the group-based acknowledgmentfeedback.

The UE may again determine feedback, which in this case includesfeedback for the PDSCH transmissions 315, 325, and 345, and format asecond feedback codebook 355 that includes bits associated with each DAIindicated in the received DAI fields. Thus, in this example, secondfeedback codebook 355 includes an ACK/NACK bit associated with DAI=1 ofthe first slot 305-a, a second ACK/NACK bit associated with DAI=2 of thesecond slot 305-b, and a third ACK/NACK bit associated with DAI=3 of thefifth slot 305-e. In this example, the PUCCH transmission 350 again maynot be successfully received at the base station (e.g., due tointerference, LBT failure, etc.). Further, the base station may attemptto transmit a fourth DCI 360 and a fifth DCI 365 in an eighth slot305-h, which may not be successfully received and decoded at the UE.

Thus, when the base station in ninth slot 305-i transmits a sixth DCI370 and associated fourth PDSCH transmission 375 that are successfullyreceived at the UE, the associated feedback parameters may be used todetermine that the UE missed fourth DCI 360 and a fifth DCI 365. In thiscase, the sixth DCI 370 includes group-based feedback parameters of K1=1(i.e., that the associated acknowledgment feedback is to be provided inthe tenth slot 305-j), DAI=2 (i.e., that indicates six DAIs due to themodulo 4 operation, and that indicates that the fourth and fifth DAIsare missed due to the NFI not being toggled), G=0 (i.e., for the samegroup as the prior DCI/PDSCH transmissions), R=0 (i.e., that feedbackfor another group is not requested), and NFI=0 (i.e., that the DAI hasnot been reset based on not being toggled from the prior DCI).

In this example the tenth slot 305-j may include uplink resources for aPUCCH transmission 380 with the group-based feedback report. In thisexample, based on the feedback parameters of the various DCIs, the UEmay determine a third feedback codebook 385 that provides ACK/NACKindications for each DAI associated with received DCIs, namely for DAIs1 through 3, provides NACK indications for each DAI that was missed atthe UE associated with the fourth DCI 360 and fifth DCI 365, andprovides an ACK/NACK indication for the sixth DAI associated with thesixth DCI 370.

Thus, in this example, even though multiple failures of uplink anddownlink transmission were experienced, the UE is able to provide all ofthe associated feedback in the third feedback codebook 385. The basestation, assuming that the third feedback codebook 385 is successfullyreceived and decoded, may then toggle the NFI and reset the DAI to onefor a subsequent DCI for a subsequent group-based feedback report.

FIG. 4 illustrates an example of a feedback timeline 400 with multiplegroups that supports group-based acknowledgment feedback techniques forwireless communications in accordance with aspects of the presentdisclosure. In some examples, feedback timeline 400 may implementaspects of wireless communications system 100 or 200. In this example, anumber of transmission slots 405 are illustrated, including a firsttransmission slot 405-a through a tenth transmission slot 405-j. In somecases, transmissions using transmission slots 405 may use licensedspectrum, unlicensed spectrum, or combinations thereof.

In this example, a first DCI 410 may be transmitted in the first slot405-a, that may include downlink scheduling information for anassociated first PDSCH transmission 415 of a first group in the firstslot 405-a. In this example, the first DCI 410 may include group-basedfeedback parameters, K1=3 (i.e., that indicates the associatedacknowledgment feedback is to be provided in fourth slot 405-d), DAI=1(i.e., that indicates the DAI is for an initial acknowledgment feedbackindicator to be included in an acknowledgment codebook), G=0 (i.e., thatidentifies first downlink transmission group), R=0 (i.e., a feedbackreport is requested for only the same group that is associated with theDCI), and NFI=0.

In the example of FIG. 4, a second DCI 420 may schedule a second PDSCHtransmission 425 of the first downlink transmission group in second slot405-b. In this example, the second DCI 420 includes group-based feedbackparameters of K1=2 (i.e., that the associated acknowledgment feedback isto be provided in the fourth slot 405-d), DAI=2 (i.e., the nextconsecutive DAI count indicating that one or more DAIs have not beenmissed), G=0 (i.e., for the same group as the first DCI 410 and firstPDSCH transmission 415), R=0 (i.e., that feedback for another group isnot requested), and NFI=0 (i.e., that the DAI has not been reset basedon not being toggled from the prior DCI).

In this example a third slot 405-c may include a third DCI 430associated with a third PDSCH transmission 435 of a second downlinktransmission group. In this example, the third DCI 430 includesgroup-based feedback parameters of K1=4 (i.e., that the associatedacknowledgment feedback is to be provided in the seventh slot 405-g),DAI=1 (i.e., an initial DAI for the second group), G=1 (i.e., for thesecond group, which is different than the group of the first DCI 410 andsecond DCI 420, R=0 (i.e., that feedback for another group is notrequested), and NFI=0.

The UE receiving the downlink transmissions may format a feedbackcodebook 445 for transmission in PUCCH transmission 440 that, in thisexample, includes bits associated with each DAI of the first group ofdownlink transmissions as indicated in the received feedback parameters.Thus, in this example, feedback codebook 445 is for the first group, andincludes an ACK/NACK bit associated with DAI=1 of the first slot 405-a,and a second ACK/NACK bit associated with DAI=2 of the second slot405-b. In this example, the PUCCH transmission 440 may not besuccessfully received at the base station (e.g., due to interference,failed LBT, etc.).

In this example, the base station may determine that the PUCCHtransmission 440 is not successfully received, and may thus maintain DCIparameters of the first group for group-based acknowledgment feedback inorder to obtain the feedback associated with the first slot 405-a andthe second slot 405-b. In this example in fifth slot 405-e, associatedwith the first downlink transmission group, the base station maytransmit a fourth DCI 450 for an associated fourth PDSCH transmission455. In this example, the fourth DCI 450 includes group-based feedbackparameters of K1=2 (i.e., that the associated acknowledgment feedback isto be provided in the seventh slot 405-g), DAI=3 (i.e., the nextconsecutive DAI count indicating that one or more DAIs have not beenmissed), G=0 (i.e., for the same group as the first DCI 410 and firstPDSCH transmission 415), R=1 (i.e., that feedback for both the firstgroup and the second group is requested), and NFI=0 (i.e., that the DAIhas not been reset based on not being toggled from the prior DCI).

In this example, in sixth slot 405-f associated with the second group ofdownlink transmissions, the base station may transmit a fifth DCI 460for an associated fifth PDSCH transmission 465. In this example, thefifth DCI 460 includes group-based feedback parameters of K1=1 (i.e.,that the associated acknowledgment feedback is to be provided in theseventh slot 405-g), DAI=2 (i.e., the next consecutive DAI count of thesecond group indicating that one or more DAIs have not been missed), G=1(i.e., for the second downlink transmission group), R=1 (i.e., thatfeedback for both the first group and the second group is requested),and NFI=0 (i.e., that the DAI has not been reset based on not beingtoggled from the prior DCI).

The seventh slot 405-g may include resources for a second PUCCHtransmission 470, for reporting of the group-based acknowledgmentfeedback. In this case, the UE may again determine feedback, which inthis case includes feedback for both the first group and the secondgroup of downlink transmissions. In this example, the UE may format afirst sub-codebook 475-a for the first group (i.e., for PDSCHtransmissions 415, 425, and 455), and format a second sub-codebook 475-bfor the second group (i.e., for PDSCH transmissions 435, and 465). Eachsub-codebook 475 includes bits associated with each DAI indicated in thereceived DAI fields for the associated group. Thus, in this example,first sub-codebook 475-a includes an ACK/NACK bit associated with firstgroup DAI=1 of the first slot 405-a, a second ACK/NACK bit associatedwith first group DAI=2 of the second slot 405-b, and a third ACK/NACKbit associated with first group DAI=3 of the fifth slot 405-e. Further,the second sub-codebook 475-b includes an ACK/NACK bit associated withsecond group DAI=1 of the third slot 405-c, and a second ACK/NACK bitassociated with second group DAI=2 of the sixth slot 405-f.

In this example, the second PUCCH transmission 470 may be successfullyreceived, and the base station may toggle the NFI field for both groupsand reset the associated DAI for each group. In this example, a sixthDCI 480 and sixth PDSCH transmission 485 associated with the secondgroup may be transmitted in ninth slot 405-i. The sixth DCI 480 mayinclude feedback parameters K1=1, DAI=1, G=1, R=0, and NFI=1, which mayindicate to the UE to transmit third PUCCH transmission 490 with anacknowledgment feedback report having codebook 495 for the second grouponly, with a single ACK/NACK associated with the sixth PDSCHtransmission 485.

FIG. 5 illustrates an example of a feedback timeline 500 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Insome examples, feedback timeline 500 may implement aspects of wirelesscommunications system 100 or 200. In this example, a number oftransmission slots 505 are illustrated, including a first transmissionslot 505-a through an eighth transmission slot 505-h. In some cases,transmissions using transmission slots 505 may use licensed spectrum,unlicensed spectrum, or combinations thereof.

In this example, a value of an NFI parameter may be toggled within onefeedback opportunity. As discussed herein, the NFI parameter may be usedto indicate a reset of an associated DAI counter for a PDSCH group forfeedback transmitted on different PUCCH transmissions. For example, asdiscussed in the examples of FIGS. 3 and 4, when a previous feedback onPUCCH is correctly received at the base station, NFI is toggled toindicate the group (i.e., DAI for the group) is reset. If NFI is nottoggled, the DAI for the group continues (i.e., the codebook for thegroup becomes larger for the next PUCCH transmission with a feedbackreport for the group). In this example, NFI is toggled within oneacknowledgment feedback transmission opportunity (i.e., within thedownlink DCIs that have a K1 value pointing to the same slot fortransmission of acknowledgment feedback for a same group). In somecases, a single codebook per downlink transmission group may betransmitted, irrespective of whether the NFI is toggled within theacknowledgment feedback transmission opportunity. In some cases, the UEis not expected to handle such a case, and in the event that the UEdetects a toggled NFI within an acknowledgment feedback transmissionopportunity, the associated PUCCH is not transmitted, and for the nextacknowledgment feedback transmission opportunity the NFI for the groupis considered to be toggled.

In other cases, the UE may still transmit a feedback report based on apredefined assumption related to a toggled NFI within an acknowledgmentfeedback transmission opportunity. For example, in the timelineillustrated in FIG. 5, a first slot 505-a may include a first DCI 510and an associated first downlink PDSCH transmission 515. The first DCImay include group-based feedback parameters of K1=1, DAI=1, G=0, R=0,and NFI=0. In this case, a second slot 505-b may include uplinkresources for a first PUCCH transmission 520 that may include a firstcodebook 525 with an ACK/NACK indication for the first PDSCHtransmission 515.

In a third slot 505-c, a second DCI 530 and a second PDSCH transmission535 may be transmitted. The second DCI 530 may include group-basedfeedback parameters of K1=5, DAI=1, G=0, R=0, and NFI=1. Suchgroup-based feedback parameters thus indicate to the UE that the firstcodebook 525 was successfully received at the base station and thatacknowledgment feedback for the first PDSCH transmission 515 does notneed to be retransmitted. In a fourth slot 505-d, a third DCI 540 andassociated third downlink PDSCH transmission 545 may be transmitted. Inthis case, the third DCI 540 includes group-based feedback parameters ofK1=4, DAI=2, G=0, R=0, and NFI=0. Thus, in this example the NFI istoggled, which normally indicates DAI reset, but the UE has nottransmitted feedback associated with prior DAIs. Continuing with theexample of FIG. 5, in a sixth slot 505-f, a fourth DCI 550 andassociated fourth PDSCH transmission 555 may be transmitted. The fourthDCI 550 may include group-based feedback parameters of K1=2, DAI=3, G=0,R=0, and NFI=1. Thus, NFI is again toggled while the UE has nottransmitted feedback associated with prior DAIs. A seventh slot 505-gmay then provide a fifth DCI 560 and associated fifth PDSCH transmission565. The fifth DCI 560 may include group-based feedback parameters ofK1=1, DAI=4, G=0, R=0, and NFI=1. An eighth slot 505-h may includeuplink resources for a second PUCCH transmission 570.

As indicated, in this example the value of NFI is toggled within anacknowledgment feedback transmission opportunity. In some cases, asingle codebook may be used to transmit the feedback report. In oneexample, the UE may consider the NFI to not be toggled within the DCIs,and thus DAI is not reset. In such an example, a second codebook 575 maybe generated for the acknowledgment feedback report that includesACK/NACK bits for each of the four DAIs associated with the second DCI530 through the fifth DCI 560. In some cases, the value of NFI for suchinstances may be determined by comparing to the previous acknowledgmentfeedback transmission opportunity to decide if current acknowledgmentfeedback for the group should assume DAI continues or not. In suchcases, the decision of whether NFI is toggled or not is based on the NFIvalue of the first DCI (among the detected DCIs that have a K1 valuepointing to the same slot for PUCCH transmission for currentacknowledgment feedback transmission opportunity), and comparing thenext acknowledgment feedback transmission opportunity to decide the same(e.g., DAI continues or not for the next feedback report), and thedecision of whether NFI is toggled or not is based on the NFI value ofthe last DCI (e.g., the fifth DCI 560 in the example of FIG. 5). Inother cases, for both the prior acknowledgment feedback transmissionopportunity and the next acknowledgment feedback transmissionopportunity, the NFI value of the last DCI or the first DCI isconsidered as the NFI value for the acknowledgment feedback transmissionopportunity. In other cases, for both the prior acknowledgment feedbacktransmission opportunity and the next acknowledgment feedbacktransmission opportunity, the NFI value for the transmission group isdecided based on majority rule among the NFI values of the received DCIs(e.g., with a tiebreaker based on a first or last DCI).

In other cases, multiple feedback codebooks may be determined based oneach toggle of NF. In the example of FIG. 5, such a technique isillustrated for third codebook 580, which may include a firstsub-codebook 580-a associated with the current state of the codebookprior to the first toggle of NFI at the third DCI 540, a secondsub-codebook 580-b associated with the current state of the codebookprior to the second toggle of the NFI at the fourth DCI 550, and a thirdsub-codebook 580-a based on the second DCI 530 through the fifth DCI560. In this example, note that the second sub-codebook 580-b includes aNACK for DAI=1, because at the time of the NFI toggle the value of DAIwas two, and thus it is uncertain whether a different DAI=1 DCI may havebeen transmitted but not received at the UE. Likewise, the thirdsub-codebook 580-c includes NACK indications for both DAI=1 and DAI=2,for the same reasons. Thus, in this technique, each time that NFI istoggled, a new sub-codebook is created for the group and DAI is reset.In some cases, each generated sub-codebook may be transmitted by the UE.In other cases, only a latest sub-codebook may be transmitted.

In some cases in which the NFI value of the last DCI (e.g., the fifthDCI 560 in the example of FIG. 5) is considered as the NFI value for theacknowledgment feedback transmission opportunity, a feedback codebookmay be determined based on the latest toggle of NFI (e.g., at the fourthDCI 550) as described above. For example, in some cases, there may be atoggle of NFI at a second DCI in a second slot of a transmissiontimeline such that an NFI at a last DCI in an eight slot is consideredas the NFI value for the acknowledgment feedback transmissionopportunity. In this case, a feedback codebook may be determined basedon the DCI occurring between and including the DCI at which the toggleoccurs (e.g., the DCI in the second slot) and the last DCI (e.g., in theeighth slot). For example, the feedback codebook may include feedbackfor the DCI in the second slot, DCI occurring after the second slot, upto and including the last DCI in the eight slot.

FIG. 6 illustrates an example of a feedback timeline 600 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Insome examples, feedback timeline 600 may implement aspects of wirelesscommunications system 100 or 200. In this example, a number oftransmission slots 605 are illustrated, including a first transmissionslot 605-a through an eighth transmission slot 605-h. In some cases,transmissions using transmission slots 605 may use licensed spectrum,unlicensed spectrum, or combinations thereof.

As discussed herein, in some cases a base station may request feedbackfor multiple groups of downlink transmissions. In such cases, it may bebeneficial to provide the UE with one or more parameters associated withthe one or more other groups of downlink transmissions. In some cases,such parameters may not be provided in DCI transmissions, and a UE thatis to transmit feedback for another group may use feedback parametersreceived only in DCIs associated with the other group. In other cases,such as illustrated in FIGS. 6 and 7, information related to the othergroup may be provided in one or more DCIs.

In this example, DCIs may be transmitted with group-based feedbackparameters that include NFI and other DAI information related to anothergroup of downlink transmissions. In such case, a two-bit NFI field maybe provided (or n-bit NFI field in the case of n groups of downlinktransmissions), an “other DAI” field may be provided (or n other DAIfields in the case of n groups of downlink transmissions).

In cases where feedback of the other downlink transmission group is notrequested (i.e., R=0), the DAI value and NFI bit for the other group(other than indicated group G) may simply be ignored. In other caseswhere feedback of the other downlink transmission group is not requestedthe UE may update the DAI and NFI of the other group according to theindication received in the DCI, but the actual feedback codebook of theother group is sent only when requested. In other cases, if the value ofNFI is equal to the previous value of NFI for the other group but theother DAI indicates one or more gaps, then the UE may generate a NACK(i.e., a dummy NACK) for each codebook position corresponding to thenumber of gaps between the end of the previous DAI value of the othergroup and the indicated DAI value for the other group. When feedback ofthe other group, or of both groups is requested, the correspondingcodebook(s) may be transmitted by the UE for the corresponding downlinktransmission group(s). In other cases, the feedback parameters providedin DCI may include DAI for other groups, but the NFI may be for only thegroup associated with the DCI (i.e., one-bit NFI). In such cases, the UEmay assume the other group NFI to be equal to the previous value of NFIfor that group.

Such techniques are illustrated in the example of FIG. 6, in which afirst DCI 610 and associated first group PDSCH transmission 615 aretransmitted in first slot 605-a. In this example, the first DCI 610includes feedback parameters of K1=3, DAI=1, G=0, R=0, NFI=00, and OtherDAI=1 (i.e., that the DAI counter for a second downlink transmissiongroup is at one). A second DCI 620 and associated first group PDSCHtransmission 625 may be transmitted in second slot 605-b. The second DCI620 includes feedback parameters of K1=2, DAI=2, G=0, R=0, NFI=00, andOther DAI=1 (i.e., that the DAI counter for a second downlinktransmission group remains at one). A third DCI 630 for the second groupand associated second group PDSCH transmission 635 may be transmitted inthird slot 605-c. The third DCI 630 includes feedback parameters ofK1=5, DAI=1, G=1, R=0, NFI=00, and Other DAI=2 (i.e., that the DAIcounter for the first group is a two).

The UE receiving the downlink transmissions may format a first groupfeedback codebook 645 for transmission in PUCCH transmission 640 that,in this example, includes bits associated with each DAI of the firstgroup of downlink transmissions as indicated in the received feedbackparameters. Thus, in this example, feedback codebook 645 is for thefirst group, and includes an ACK/NACK bit associated with DAI=1 of thefirst slot 605-a, and a second ACK/NACK bit associated with DAI=2 of thesecond slot 605-b. In this example, the PUCCH transmission 640 may notbe successfully received at the base station (e.g., due to interference,failed LBT, etc.).

In this example, the base station may determine that the PUCCHtransmission 640 is not successfully received, and may thus maintain DCIparameters of the first group for group-based acknowledgment feedback inorder to obtain the feedback associated with the first slot 605-a andthe second slot 605-b. In this example in fifth slot 605-e, associatedwith the first downlink transmission group, the base station maytransmit a fourth DCI 650, that may not be successfully received anddecoded at the UE. Further, in this example, the base station maytransmit a fifth DCI 655 in sixth slot 605-f associated with the firstgroup, that may not be successfully received and decoded at the UE.

At the seventh slot 605-g, a sixth DCI 660 may be transmitted, alongwith fourth PDSCH transmission 665 associated with the second group. Thesixth DCI 660 includes feedback parameters of K1=1, DAI=2, G=1, R=1,NFI=00, and Other DAI=4 (i.e., the DAI of the first group is four). Inthis example, the UE may format a first sub-codebook 675-a for the firstgroup (i.e., for PDSCH transmissions 615, 625, and unreceivedtransmissions for DAI=3 and DAI=4), and format a second sub-codebook675-b for the second group (i.e., for PDSCH transmissions 635, and 665).Each sub-codebook 675 includes bits associated with each DAI indicatedin the received DAI fields for the associated group. Thus, in thisexample, first sub-codebook 675-a includes an ACK/NACK bit associatedwith first group DAI=1 of the first slot 605-a, a second ACK/NACK bitassociated with first group DAI=2 of the second slot 605-b, and NACKbits associated with first group DAI=3 and DAI=4 that were not receivedat the UE but indicated as having been sent in the sixth DCI 660.Further, the second sub-codebook 675-b includes an ACK/NACK bitassociated with second group DAI=1 of the third slot 605-c, and a secondACK/NACK bit associated with second group DAI=2 of the seventh slot605-g. Thus, the Other DAI indication provided in the group-basedfeedback parameters may allow the UE to report negative acknowledgmentsooner than would be reported if the other DAI was not indicated to theUE, which may enhance operation of a wireless communications systemrelative to cases where such NACK indications would be provided later.

FIG. 7 illustrates another example of a feedback timeline 700 thatsupports group-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Insome examples, feedback timeline 700 may implement aspects of wirelesscommunications system 100 or 200. In this example, a number oftransmission slots 705 are illustrated, including a first transmissionslot 705-a through an eighth transmission slot 705-h. In some cases,transmissions using transmission slots 705 may use licensed spectrum,unlicensed spectrum, or combinations thereof.

As discussed with respect to FIG. 6, in some cases, a base station mayrequest feedback for multiple groups of downlink transmissions, and mayprovide the UE with one or more parameters associated with the one ormore other groups of downlink transmissions. In the example of FIG. 6,the value of the NFI bit for each group was equal to a previous NFIvalue. In cases where the value of the NFI bit changes, such asillustrated in FIG. 7, a UE should generate a NACK indication (e.g., adummy NACK) up to the value of indicated DAI for that group, and theprevious DAI value of that group is not used. Such a situation mayindicate, for example, that all the DCIs of the other group are missed.

In the example of FIG. 7, a first DCI 710 and associated first groupPDSCH transmission 715 are transmitted in first slot 705-a. In thisexample, the first DCI 710 includes feedback parameters of K1=1, DAI=1,G=0, R=0, NFI=00, and Other DAI=1 (e.g., the DAI counter for a seconddownlink transmission group is at one). The second slot 705-b mayinclude resources for a first PUCCH transmission 720, which may includea first codebook 725 that provides a feedback report for the firstdownlink transmission group.

A second DCI 730 may be transmitted bot not received at UE in third slot705-c, and a third DCI 735 be transmitted bot not received at UE infourth slot 705-d. In this example, fifth slot 704-e may include uplinkresources for a second PUCCH transmission 740, but the UE may nottransmit such a transmission because there is no feedback to report.

At the seventh slot 705-g, a fourth DCI 745 and second PDSCHtransmission 750 associated with the second downlink transmission groupmay be transmitted. The fourth DCI 745 includes feedback parameters ofK1=1, DAI=1, G=1, R=1, NFI=01, and Other DAI=2 (i.e., that the DAIcounter for the first downlink transmission group is at two, which mayindicate to the UE that two DCIs were missed).

The UE receiving the downlink transmissions may format a second groupfeedback codebook 760 for transmission in PUCCH transmission 755 ineighth slot 705-h. In this example, the second group feedback codebook760 may include a first sub-codebook 760-a associated with the firstdownlink transmission group that indicates NACK for each DAI that wasnot received at the UE. The indication of the toggled NFI for the firstgroup that is provided in the fourth DCI 745, along with the indicationthat the other DAI is two, indicates to the UE that the DAI was resetand that two DCIs had been transmitted, which the UE uses to report theNACK indications. In this example, second sub-codebook 760-b may provideacknowledgment feedback for DAI=1 of the second group of downlinktransmissions. Thus, the Other DAI indication provided in thegroup-based feedback parameters, along with the NFI indication of theother group, may allow the UE to report negative acknowledgment soonerthan would be reported if the other DAI was not indicated to the UE,which may enhance operation of a wireless communications system relativeto cases where such NACK indications would be provided later.

As discussed, in some cases, feedback for a different downlinktransmission group may be requested in a DCI for a first downlinktransmission group (e.g., based on a value of the parameter R). In somecases, DCIs with group-based feedback parameters may not include aparameter for R. In such cases, sending feedback for more than one groupin a PUCCH may be accomplished through two or more DCIs indicating K1values that point to the same slot for PUCCH transmission, and thatindicate different groups (i.e., have different G values). In suchcases, a UE may determine that multiple feedback codebooks associatedwith different downlink transmission groups are to be generated andtransmitted. In cases where such a parameter R is not provided withgroup-based feedback parameters, NFI indications and Other DAIindications for the other group may also not be included with thegroup-based feedback parameters, and the size of the group-basedfeedback parameters may be reduced relative to cases where suchparameters are provided.

In other cases, the group-based feedback parameters field R may bepresent in the DCI and indicate whether feedback for other groups isrequested or not. In some situations, a value of R may change within thedetected DCIs that have a K1 value pointing to the same slot for PUCCHtransmission (e.g., due to an error at the base station, an error indecoding the group-based feedback parameters, interference with the DCItransmission, etc.). In some cases, if the value of R changes in such amanner, the value in the latest received DCI may be considered todetermine if feedback for other groups are requested. In some cases, theUE may not be expected to handle the case where initially feedback forother groups is requested (R=1) and then in a next DCI feedback is notrequested (R=0), which may result in an error case and the UE may nottransmit PUCCH with the feedback report. In such a case, a base stationmay have a restriction that the UE is not expected to receive DCIsscheduling PDSCHs that belong to different PDSCH groups (e.g., G=0 andG=1) and point to the same slot for feedback transmission. In othercases, if at least one value of R in received DCIs indicates feedbackfor other groups is to be transmitted, the UE may transmit feedback forthe other groups.

In cases where feedback for two or more downlink transmission groups istransmitted, a rule may be defined for appending the codebook of firstgroup and second group. In some cases, when feedback for more than onegroup exists, ordering of placing the two codebooks in the feedbackpayload may be based on a group index of each downlink transmissiongroup. For example, the UE may generate the feedback codebook byappending the codebook for G=1 to the codebook for G=0. In other cases,the codebook for the other group is placed after the codebook of currentgroup (e.g., if the DCI for group G=1 requests feedback for group G=0,the UE may generate the feedback codebook by appending the codebook forG=0 to the codebook for G=1. Thus, multiple codebooks for differentdownlink transmission groups may be multiplexed in a feedback report.

The examples discussed with respect to FIGS. 3 through 7 describe thatDCI may include various group-based feedback parameters. In some cases,such DCI transmissions may have a DCI format that is associated withgroup-based downlink feedback (e.g., DCI Format 1_1). In some cases,however, one or more downlink transmissions may be scheduled with afallback DCI (e.g., DCI format 1_0) that does not include group-basedfeedback parameters. According to some aspects of the presentdisclosure, group-based acknowledgment feedback may still be used withsuch fallback DCI. In some cases, when dynamic group-basedacknowledgment feedback is configured (e.g., configured at an RRCestablishment, and enabled through RRC signaling), if a UE receives aDCI scheduling PDSCH and the DCI format does not have additional fieldsfor information related to the dynamic group-based acknowledgmentfeedback (i.e., a fallback DCI), the UE may determine group-basedacknowledgment feedback parameters according to one or more apredetermined rules.

In some cases, one or more existing fields of the fallback DCI may bereused to indicate one or more group-based acknowledgment feedbackparameters. For example, one or more bits of a PUCCH resource indicator(PRI) field, one or more bits of frequency domain resource assignment(FDRA) or a time domain resource assignment (TDRA), or combinationsthereof may be used for to provide information related to thegroup-based acknowledgment feedback parameters. In other cases, the UEmay assume a fixed value for the group-based acknowledgment feedbackparameters that are missing from the fallback DCI. For example, the UEmay assume that PDSCH always belongs to the first group (G=0 isassumed), and NFI is not toggled (same NFI as the previous DCI isassumed). Further, in cases where R, NFI, and other DAI are providedwith the group-based acknowledgment feedback parameters, the UE mayassume that for fallback DCI, R=0 (feedback for other group notrequested), and no assumption or update is made for other NFI and otherDAI.

In other cases, group-based acknowledgment feedback corresponding toPDSCHs scheduled by fallback DCIs may be separately constructed fromfeedback corresponding to PDSCHs scheduled by DCI that includes thegroup-based acknowledgment feedback parameters. In some cases, as a cDAIfield may be present in the fallback DCI format, DAI may be appliedseparately for different DCI formats. In some cases, where such feedbackis constructed separately, for a given group-based acknowledgmentfeedback reporting, the UE may expect only PDSCHs scheduled by fallbackDCI or only by non-fallback DCI, and a base station may format DCIsaccordingly. In other cases, for a given group-based acknowledgmentfeedback reporting, the UE may have both PDSCHs scheduled by fallbackDCI or by non-fallback DCI, in which case up to three feedback codebooksmay be possible (e.g., a first codebook for PDSCHs scheduled by fallbackDCI, a second codebook for non-fallback DCI with G=0, and a thirdcodebook for non-fallback DCI with G=1). In such cases, group-basedacknowledgment feedback may be used along with fallback DCI, which mayenhance system flexibility and feedback performance/latency. In somecases, if each DCI for a feedback transmission is a fallback DCI (i.e.,all the DCIs that point to the same slot for an associatedacknowledgment feedback transmission are fallback DCIs), regularnon-group-based acknowledgment feedback may be transmitted in thefeedback transmission, and subsequent group-based feedback may beprovided for one or more PDSCH transmissions from prior to the fallbackDCI transmissions. An example of such a technique is described withreference to FIG. 8.

FIG. 8 illustrates an example of a feedback timeline 800 that supportsgroup-based and non-group-based acknowledgment feedback techniques forwireless communications in accordance with aspects of the presentdisclosure. In some examples, feedback timeline 800 may implementaspects of wireless communications system 100 or 200. In this example, anumber of transmission slots 805 are illustrated, including a firsttransmission slot 805-a through a ninth transmission slot 805-i. In somecases, transmissions using transmission slots 805 may use licensedspectrum, unlicensed spectrum, or combinations thereof.

In this example, a first DCI 810 may be transmitted in the first slot805-a, that may include downlink scheduling information for anassociated first PDSCH transmission 815 of a first group in the firstslot 805-a. In this example, the first DCI 810 may include group-basedfeedback parameters, K1=2 (i.e., that indicates the associatedacknowledgment feedback is to be provided in third slot 805-c), DAI=1(i.e., that indicates the DAI is for an initial acknowledgment feedbackindicator to be included in an acknowledgment codebook of the firstgroup), G=0 (i.e., that identifies first downlink transmission group),R=1 (i.e., a feedback report is requested for multiple groups), andNFI=0.

In the example of FIG. 8, a second DCI 820 may schedule a second PDSCHtransmission 825 that is in the second downlink transmission group insecond slot 805-b. In this example, the second DCI 820 includesgroup-based feedback parameters of K1=1 (i.e., that the associatedacknowledgment feedback is to be provided in the third slot 805-c),DAI=1 (i.e., that indicates the DAI is for an initial acknowledgmentfeedback indicator to be included in an acknowledgment codebook of thefirst group), G=1 (i.e., for the second group, which is different thanthe group of the first DCI 810), R=1 (i.e., a feedback report isrequested for multiple groups), and NFI=0.

The UE receiving the downlink transmissions may format feedbackcodebooks 835 and 840 for transmission in PUCCH transmission 830 that,in this example, includes bits associated with each of the first andsecond groups of downlink transmissions as indicated in the receivedfeedback parameters.

In this example, the base station may transmit a fallback DCI 845 (e.g.,DCI format 1_0) and PDSCH transmission 850 in the fourth slot 805-d, andalso a fallback DCI 855 and PDSCH transmission 860 in the fifth slot805-e. Both fallback DCIs 845 and 855 may indicate that associatedacknowledgment feedback is to be provided in sixth slot 805-f. The UEmay transmit PUCCH 865 in the sixth slot 805-f, which may include aregular dynamic feedback codebook 870 for non-group-based feedback. Insuch case, the feedback from the first slot 805-a and the second slot805-b may not be provided in the PUCCH 865 transmission. Thus, theregular dynamic codebook may be used in an acknowledgment feedbackopportunity in cases where all of the DCIs associated with thatacknowledgment feedback opportunity are fallback DCIs. In cases whereone DCI is a fallback DCI and another DCI is for group-based feedback,group-based feedback may be transmitted in a manner similarly asdiscussed with respect to FIG. 7. For example, a PDSCH group scheduledby the DCI format 1_0 may be assumed to be the first PDSCH group, NFI ofthe first PDSCH group may be assumed as not changed by the DCI, and itmay be assumed that the DCI does not request feedback for the otherPDSCH group.

Continuing with this example, in seventh slot 805-g, associated with thefirst downlink transmission group, the base station may transmit a DCI875 for an associated second group-based PDSCH transmission 880 of thefirst transmission group. In this example, the DCI 875 includes feedbackparameters of K1=2 (i.e., that the associated acknowledgment feedback isto be provided in the ninth slot 805-i), DAI=2 (i.e., the nextconsecutive DAI count), G=0 (i.e., for the same group as the first DCI810 and first PDSCH transmission 815), R=1 (i.e., that feedback for boththe first group and the second group is requested), and NFI=0 (i.e.,that the DAI has not been reset based on not being toggled from theprior DCI). In this example, in eighth slot 805-h, associated with thesecond group of downlink transmissions, the base station may transmit aDCI 885 for an associated second group-based PDSCH transmission 890 ofthe second transmission group. In this example, the DCI 885 includesfeedback parameters of K1=1 (i.e., that the associated acknowledgmentfeedback is to be provided in the ninth slot 805-i), DAI=2 (i.e., thenext consecutive DAI count of the second group), G=1 (i.e., for thesecond downlink transmission group), R=1 (i.e., that feedback for boththe first group and the second group is requested), and NFI=0 (i.e.,that the DAI has not been reset based on not being toggled from theprior DCI).

The ninth slot 805-i may include resources for a second group-basedPUCCH transmission 895, for reporting of the group-based acknowledgmentfeedback. In this case, the UE may again determine feedback, which inthis case includes feedback for both the first group and the secondgroup of downlink transmissions. In this example, the UE may format oneor more feedback codebooks 897 for the first group and/or second group.In this example, separate sub-codebooks for the first group and secondgroup would be included, but in other examples only one codebook may beincluded. In such case, the feedback codebook(s) 897 may includeacknowledgment feedback for the slots prior to the fallback DCItransmissions, namely the first slot 805-a and second slot 805-b in thisexample. Thus, in such examples, regular (i.e., non-group-based) dynamiccodebook feedback may be used when all DCIs for an acknowledgmentfeedback opportunity are fallback DCIs, and the group-based codebookfeedback may be used before and after the regular dynamic codebookfeedback, where group-based feedback may be associated withtransmissions that are before and/or after the DCIs with the fallbackDCI.

In some cases, for the acknowledgment feedback opportunity in the ninthslot 805-i, (i.e., the group-based feedback transmission following thefeedback for the fallback DCIs), the feedback bits of the sixth slot805-f may not be retransmitted, but feedback bits for earliertransmissions scheduled with group-based DCI from the first slot 805-aand the second slot 805-b may be retransmitted in the feedbackcodebook(s) 897. In some cases, the NFI for the one or more PDSCH groupsmay be assumed to be toggled in which case feedback bits for earliertransmissions scheduled with group-based DCI from the first slot 805-aand the second slot 805-b may not be retransmitted in the feedbackcodebook(s) 897. In other cases, to determine whether NFI is toggled ornot, previous DCIs that included NFI for a group are considered (i.e.,before the fallback DCIs).

FIG. 9 shows a block diagram 900 of a device 905 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 905 may be an example of aspects of a UE 115 as described herein.The device 905 may include a receiver 910, a communications manager 915,and a transmitter 920. The device 905 may also include a processor. Eachof these components may be in communication with one another (e.g., viaone or more buses).

The receiver 910 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to group-basedacknowledgment feedback techniques for wireless communications, etc.).Information may be passed on to other components of the device 905. Thereceiver 910 may be an example of aspects of the transceiver 1220described with reference to FIG. 12. The receiver 910 may utilize asingle antenna or a set of antennas.

In some cases, the communications manager 915 may receive a firstdownlink control information transmission from a base station thatprovides a first set of group-based acknowledgment feedback parametersassociated with a first downlink transmission, where the first set ofgroup-based acknowledgment feedback parameters includes a first newacknowledgment feedback indicator and a first feedback timing thatindicates a first uplink transmission that is to include a firstgroup-based acknowledgment feedback, receive a second downlink controlinformation transmission from the base station that provides a secondset of group-based acknowledgment feedback parameters associated with asecond downlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, and determine, based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time, the firstgroup-based acknowledgment feedback.

In some cases, the communications manager 915 may also receive adownlink control information transmission from a base station thatprovides a set of group-based acknowledgment feedback parameters, wherethe set of group-based acknowledgment feedback parameters includes agroup indicator that identifies at least a first group of downlinktransmissions to be included in a first group-based acknowledgementfeedback transmission, a first downlink assignment indicator thatidentifies one or more downlink transmissions of the first group ofdownlink transmissions, a second downlink assignment indicator thatidentifies one or more downlink transmissions of a second group ofdownlink transmissions, a first new acknowledgment feedback indicatorthat identifies whether the first downlink assignment indicator isreset, and a second new acknowledgment feedback indicator associatedwith the second group of downlink transmissions, receive the one or moredownlink transmissions of the first group of downlink transmissions,determine, based on the first downlink assignment indicator and thefirst new acknowledgment feedback indicator, first acknowledgmentfeedback associated with the first group of downlink transmissions forinclusion with the first group-based acknowledgement feedbacktransmission, update the second group-based acknowledgement feedbackassociated with the second group of downlink transmissions based on thedetermining, and transmit the first group-based acknowledgement feedbacktransmission to the base station.

In some cases, the communications manager 915 may also receive a firstdownlink control information transmission from a base station thatprovides a first set of group-based acknowledgment feedback parameters,where the first set of group-based acknowledgment feedback parametersincludes a first group indicator for a first group of downlinktransmissions, and a first feedback timing that indicates a first uplinktransmission is to include a first group-based acknowledgment feedbackassociated with the first group of downlink transmissions, receive asecond downlink control information transmission from the base stationthat provides a second set of group-based acknowledgment feedbackparameters, where the second set of group-based acknowledgment feedbackparameters includes a second group indicator for a second group ofdownlink transmissions, and a second feedback timing that indicates thefirst uplink transmission is to include one or more of the firstgroup-based acknowledgement feedback or a second group-basedacknowledgment feedback associated with the second group of downlinktransmissions, and determine, based on the first feedback timing and thesecond feedback timing, that the first uplink transmission is to includeboth the first group-based acknowledgement feedback and the secondgroup-based acknowledgment feedback.

In some cases, the communications manager 915 may also receive, from abase station, configuration information for group-based acknowledgmentfeedback for one or more groups of downlink transmissions to the UE,where one or more parameters associated with the group-basedacknowledgment feedback are indicated in a first set of fields of afirst downlink control information format, and are absent from a secondset of fields of a second downlink control information format that isdifferent than the first set of fields, where the first set of fieldsincludes a first subset of information fields that are in addition tothe second set of fields, receive a downlink control informationtransmission from the base station having the second downlink controlinformation format, determine, based on using a predetermined value foreach field of the first subset of information fields, firstacknowledgment feedback associated with at least a first group ofdownlink transmissions, and transmit the first acknowledgment feedbackto the base station. The communications manager 915 may be an example ofaspects of the communications manager 1210 described herein.

In some cases, the communications manager 915 may receive a firstdownlink control information transmission from a base station that isassociated with a first group-based downlink transmission and a firstacknowledgment feedback occasion, receive a second downlink controlinformation transmission, subsequent to the first downlink controlinformation transmission, that is associated with a secondnon-group-based downlink transmission and a second acknowledgmentfeedback occasion, receive a third downlink control informationtransmission, subsequent to the second downlink control informationtransmission, that is associated with a third group-based downlinktransmission and a third acknowledgment feedback occasion, transmitnon-group-based acknowledgment feedback associated with the secondnon-group-based downlink transmission in the second acknowledgmentfeedback occasion, and transmit group-based acknowledgment feedbackassociated with one or more or the first group-based downlinktransmission or the third group-based downlink transmission in the thirdacknowledgment feedback occasion. The communications manager 915 may bean example of aspects of the communications manager 1210 describedherein.

The actions performed by the communications manager 915 as describedherein may be implemented to realize one or more potential advantages.For example, a UE may implement group-based feedback reports to transmitfeedback for all of the feedback processes that are configured at the UE115. Thus, techniques such as discussed herein may allow for efficientacknowledgment feedback that may help reduce latency and enhance overallsystem throughput in a wireless communication system. Implementinggroup-based feedback reports may provide improved quality andreliability of service at the UE 115, as latency and the number ofseparate resources allocated to the UE 115 may be reduced. Thecommunications manager 915, or its sub-components, may be implemented inhardware, code (e.g., software or firmware) executed by a processor, orany combination thereof. If implemented in code executed by a processor,the functions of the communications manager 915, or its sub-componentsmay be executed by a general-purpose processor, a digital signalprocessor (DSP), an application-specific integrated circuit (ASIC), afield programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described in thepresent disclosure.

The communications manager 915, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 915, or its sub-components, may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In some examples, the communications manager 915, or its sub-components,may be combined with one or more other hardware components, includingbut not limited to an input/output (I/O) component, a transceiver, anetwork server, another computing device, one or more other componentsdescribed in the present disclosure, or a combination thereof inaccordance with various aspects of the present disclosure.

The transmitter 920 may transmit signals generated by other componentsof the device 905. In some examples, the transmitter 920 may becollocated with a receiver 910 in a transceiver module. For example, thetransmitter 920 may be an example of aspects of the transceiver 1220described with reference to FIG. 12. The transmitter 920 may utilize asingle antenna or a set of antennas.

FIG. 10 shows a block diagram 1000 of a device 1005 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1005 may be an example of aspects of a device 905, or a UE 115 asdescribed herein. The device 1005 may include a receiver 1010, acommunications manager 1015, and a transmitter 1040. The device 1005 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1010 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to group-basedacknowledgment feedback techniques for wireless communications, etc.).Information may be passed on to other components of the device 1005. Thereceiver 1010 may be an example of aspects of the transceiver 1220described with reference to FIG. 12. The receiver 1010 may utilize asingle antenna or a set of antennas.

The communications manager 1015 may be an example of aspects of thecommunications manager 915 as described herein. The communicationsmanager 1015 may include a group-based feedback manager 1020, a feedbackdetermination manager 1025, a downlink transmission manager 1030, and afeedback transmission manager 1035. The communications manager 1015 maybe an example of aspects of the communications manager 1210 describedherein.

In some cases, the group-based feedback manager 1020 may receive a firstdownlink control information transmission from a base station thatprovides a first set of group-based acknowledgment feedback parametersassociated with a first downlink transmission, where the first set ofgroup-based acknowledgment feedback parameters includes a first newacknowledgment feedback indicator and a first feedback timing thatindicates a first uplink transmission that is to include a firstgroup-based acknowledgment feedback and receive a second downlinkcontrol information transmission from the base station that provides asecond set of group-based acknowledgment feedback parameters associatedwith a second downlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback. The feedback determination manager 1025 maydetermine, based on which of the first new acknowledgment feedbackindicator or the second new acknowledgment feedback indicator isreceived earliest or latest in time, the first group-basedacknowledgment feedback. Based on receiving the first downlink controlinformation transmission and the second downlink control informationtransmission, a processor of a UE 115 (e.g., controlling the receiver1010, the transmitter 1040, or the transceiver 1220 as described withreference to FIG. 12) may efficiently determine the first group-basedacknowledgment feedback. The processor of the UE 115 may turn on one ormore processing units for receiving the first downlink controlinformation transmission and the second downlink control informationtransmission, increase a processing clock, or a similar mechanism withinthe UE 115. As such, when the first downlink control informationtransmission and the second downlink control information transmissionare received, the processor may be ready to respond more efficientlythrough the reduction of a ramp up in processing power.

In some cases, the group-based feedback manager 1020 may receive adownlink control information transmission from a base station thatprovides a set of group-based acknowledgment feedback parameters, wherethe set of group-based acknowledgment feedback parameters includes agroup indicator that identifies at least a first group of downlinktransmissions to be included in a first group-based acknowledgementfeedback transmission, a first downlink assignment indicator thatidentifies one or more downlink transmissions of the first group ofdownlink transmissions, a second downlink assignment indicator thatidentifies one or more downlink transmissions of a second group ofdownlink transmissions, a first new acknowledgment feedback indicatorthat identifies whether the first downlink assignment indicator isreset, and a second new acknowledgment feedback indicator associatedwith the second group of downlink transmissions. The downlinktransmission manager 1030 may receive the one or more downlinktransmissions of the first group of downlink transmissions. The feedbackdetermination manager 1025 may determine, based on the first downlinkassignment indicator and the first new acknowledgment feedbackindicator, first acknowledgment feedback associated with the first groupof downlink transmissions for inclusion with the first group-basedacknowledgement feedback transmission. The feedback transmission manager1035 may update the second group-based acknowledgement feedbackassociated with the second group of downlink transmissions based on thedetermining. The feedback transmission manager 1035 may transmit thefirst group-based acknowledgement feedback transmission to the basestation.

In some cases, the group-based feedback manager 1020 may receive a firstdownlink control information transmission from a base station thatprovides a first set of group-based acknowledgment feedback parameters,where the first set of group-based acknowledgment feedback parametersincludes a first group indicator for a first group of downlinktransmissions, and a first feedback timing that indicates a first uplinktransmission is to include a first group-based acknowledgment feedbackassociated with the first group of downlink transmissions and receive asecond downlink control information transmission from the base stationthat provides a second set of group-based acknowledgment feedbackparameters, where the second set of group-based acknowledgment feedbackparameters includes a second group indicator for a second group ofdownlink transmissions, and a second feedback timing that indicates thefirst uplink transmission is to include one or more of the firstgroup-based acknowledgement feedback or a second group-basedacknowledgment feedback associated with the second group of downlinktransmissions. The feedback determination manager 1025 may determine,based on the first feedback timing and the second feedback timing, thatthe first uplink transmission is to include both the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.

In some cases, the group-based feedback manager 1020 may receive, from abase station, configuration information for group-based acknowledgmentfeedback for one or more groups of downlink transmissions to the UE,where one or more parameters associated with the group-basedacknowledgment feedback are indicated in a first set of fields of afirst downlink control information format, and are absent from a secondset of fields of a second downlink control information format that isdifferent than the first set of fields, where the first set of fieldsincludes a first subset of information fields that are in addition tothe second set of fields, receive a downlink control informationtransmission from the base station having the second downlink controlinformation format, and determine, based on using a predetermined valuefor each field of the first subset of information fields, firstacknowledgment feedback associated with at least a first group ofdownlink transmissions. The feedback transmission manager 1035 maytransmit the first acknowledgment feedback to the base station.

In some cases, the downlink transmission manager 1030 may receive afirst downlink control information transmission from a base station thatis associated with a first group-based downlink transmission and a firstacknowledgment feedback occasion, receive a second downlink controlinformation transmission, subsequent to the first downlink controlinformation transmission, that is associated with a secondnon-group-based downlink transmission and a second acknowledgmentfeedback occasion, and receive a third downlink control informationtransmission, subsequent to the second downlink control informationtransmission, that is associated with a third group-based downlinktransmission and a third acknowledgment feedback occasion. The feedbacktransmission manager 1035 may transmit non-group-based acknowledgmentfeedback associated with the second non-group-based downlinktransmission in the second acknowledgment feedback occasion and transmitgroup-based acknowledgment feedback associated with one or more or thefirst group-based downlink transmission or the third group-baseddownlink transmission in the third acknowledgment feedback occasion.

The transmitter 1040 may transmit signals generated by other componentsof the device 1005. In some examples, the transmitter 1040 may becollocated with a receiver 1010 in a transceiver module. For example,the transmitter 1040 may be an example of aspects of the transceiver1220 described with reference to FIG. 12. The transmitter 1040 mayutilize a single antenna or a set of antennas.

FIG. 11 shows a block diagram 1100 of a communications manager 1105 thatsupports group-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Thecommunications manager 1105 may be an example of aspects of acommunications manager 915, a communications manager 1015, or acommunications manager 1210 described herein. The communications manager1105 may include a group-based feedback manager 1110, a feedbackdetermination manager 1115, a group determination manager 1120, afeedback transmission manager 1125, a downlink transmission manager1130, and an NFI determination component 1135. Each of these modules maycommunicate, directly or indirectly, with one another (e.g., via one ormore buses).

The group-based feedback manager 1110 may receive a first downlinkcontrol information transmission from a base station that provides afirst set of group-based acknowledgment feedback parameters associatedwith a first downlink transmission, where the first set of group-basedacknowledgment feedback parameters includes a first new acknowledgmentfeedback indicator and a first feedback timing that indicates a firstuplink transmission that is to include a first group-basedacknowledgment feedback.

In some examples, the group-based feedback manager 1110 may receive asecond downlink control information transmission from the base stationthat provides a second set of group-based acknowledgment feedbackparameters associated with a second downlink transmission, where thesecond set of group-based acknowledgment feedback parameters includes asecond new acknowledgment feedback indicator that is different than thefirst new acknowledgment feedback indicator, and a second feedbacktiming that indicates the first uplink transmission is to include thefirst group-based acknowledgment feedback.

In some examples, the group-based feedback manager 1110 may receive adownlink control information transmission from a base station thatprovides a set of group-based acknowledgment feedback parameters, wherethe set of group-based acknowledgment feedback parameters includes agroup indicator that identifies at least a first group of downlinktransmissions to be included in a first group-based acknowledgementfeedback transmission, a first downlink assignment indicator thatidentifies one or more downlink transmissions of the first group ofdownlink transmissions, a second downlink assignment indicator thatidentifies one or more downlink transmissions of a second group ofdownlink transmissions, a first new acknowledgment feedback indicatorthat identifies whether the first downlink assignment indicator isreset, and a second new acknowledgment feedback indicator associatedwith the second group of downlink transmissions.

In some examples, the group-based feedback manager 1110 may receive afirst downlink control information transmission from a base station thatprovides a first set of group-based acknowledgment feedback parameters,where the first set of group-based acknowledgment feedback parametersincludes a first group indicator for a first group of downlinktransmissions, and a first feedback timing that indicates a first uplinktransmission is to include a first group-based acknowledgment feedbackassociated with the first group of downlink transmissions.

In some examples, the group-based feedback manager 1110 may receive asecond downlink control information transmission from the base stationthat provides a second set of group-based acknowledgment feedbackparameters, where the second set of group-based acknowledgment feedbackparameters includes a second group indicator for a second group ofdownlink transmissions, and a second feedback timing that indicates thefirst uplink transmission is to include one or more of the firstgroup-based acknowledgement feedback or a second group-basedacknowledgment feedback associated with the second group of downlinktransmissions.

In some examples, the group-based feedback manager 1110 may receive,from a base station, configuration information for group-basedacknowledgment feedback for one or more groups of downlink transmissionsto the UE, where one or more parameters associated with the group-basedacknowledgment feedback are indicated in a first set of fields of afirst downlink control information format, and are absent from a secondset of fields of a second downlink control information format that isdifferent than the first set of fields, where the first set of fieldsincludes a first subset of information fields that are in addition tothe second set of fields.

In some examples, the group-based feedback manager 1110 may receive adownlink control information transmission from the base station havingthe second downlink control information format. In some examples, thegroup-based feedback manager 1110 may determine, based on using apredetermined value for each field of the first subset of informationfields, first acknowledgment feedback associated with at least a firstgroup of downlink transmissions.

In some examples, the group-based feedback manager 1110 may identifythat the second new acknowledgment feedback indicator being differentthan the first new acknowledgment feedback indicator for the firstgroup-based acknowledgment feedback corresponds to an error case.

In some examples, the group-based feedback manager 1110 may discontinuegenerating the first group-based acknowledgment feedback to betransmitted in the first uplink transmission.

In some examples, the group-based feedback manager 1110 may transmit thefirst group-based acknowledgement feedback and the second group-basedacknowledgment feedback when at least one of the first set ofgroup-based acknowledgment feedback parameters or the second set ofgroup-based acknowledgment feedback parameters indicates a request forboth the first group of downlink transmissions and the second group ofdownlink transmissions.

In some examples, the group-based feedback manager 1110 may determinethat the second new acknowledgment feedback indicator resets the firstgroup-based acknowledgment feedback for a subsequent second uplinktransmission that is to include group-based acknowledgment feedback.

In some examples, the group-based feedback manager 1110 may determinethat the group indicator identifies only the first group of downlinktransmissions are to be included in the first group-basedacknowledgement feedback transmission.

In some examples, the group-based feedback manager 1110 may ignore thesecond downlink assignment indicator and the second new acknowledgmentfeedback indicator associated with the second group of downlinktransmissions.

In some examples, the group-based feedback manager 1110 may determinethat the group indicator identifies that both the first group ofdownlink transmissions and the second group of downlink transmissionsare to be included in the first group-based acknowledgement feedbacktransmission.

In some examples, the group-based feedback manager 1110 may receive,from the base station, an indication to enable the group-basedacknowledgment feedback, and where the second set of fields of thesecond downlink control information format are interpreted differentlybased on whether the group-based acknowledgment feedback is enabled ordisabled at the UE.

In some cases, the set of group-based acknowledgment feedback parametersfurther includes second downlink assignment indicator that identifiesone or more downlink transmissions of a second group of downlinktransmissions and a second new acknowledgment feedback indicatorassociated with the second group of downlink transmissions.

In some cases, the second downlink control information format is afallback downlink control information format.

In some cases, the first subset of information fields include one ormore of a group indicator field, a new acknowledgment feedback indicatorfield, or a request field that indicates acknowledgment feedback isrequested for one or more of multiple different groups of downlinktransmissions.

In some cases, the predetermined value for the group indicator fieldcorresponds to a downlink transmission group associated with thedownlink control information transmission, the predetermined value forthe new acknowledgment feedback indicator field corresponds to a priorvalue of the new acknowledgment feedback indicator field, thepredetermined value for the request field corresponds to a value thatindicates acknowledgment feedback is not requested for another group ofdownlink transmissions.

The feedback determination manager 1115 may determine, based on which ofthe first new acknowledgment feedback indicator or the second newacknowledgment feedback indicator is received earliest or latest intime, the first group-based acknowledgment feedback.

In some examples, the feedback determination manager 1115 may determine,based on the first downlink assignment indicator and the first newacknowledgment feedback indicator, first acknowledgment feedbackassociated with the first group of downlink transmissions for inclusionwith the first group-based acknowledgement feedback transmission.

In some examples, the feedback determination manager 1115 may determine,based on the first feedback timing and the second feedback timing, thatthe first uplink transmission is to include both the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.

In some examples, the feedback determination manager 1115 may determinea first acknowledgment (ACK)/negative-acknowledgment (NACK) to bereported as feedback for the first downlink transmission and a secondACK/NACK to be reported as feedback for the second downlinktransmission. In some examples, the feedback determination manager 1115may identify that the second new acknowledgment feedback indicator beingdifferent than the first new acknowledgment feedback indicator for thefirst group-based acknowledgment feedback is interpreted as the newacknowledgment feedback indicator being untoggled from the first newacknowledgment feedback indicator. In some examples, the feedbackdetermination manager 1115 may format the first group-basedacknowledgment feedback to include the first ACK/NACK and the secondACK/NACK based on the first new acknowledgment feedback indicator or thesecond new acknowledgment feedback indicator. In some examples, thefeedback determination manager 1115 may transmit a latest subset offeedback information associated with a latest received newacknowledgment feedback indicator

In some examples, the feedback determination manager 1115 may format afirst subset of feedback information associated with the first newacknowledgment feedback indicator in the first group-basedacknowledgment feedback and a second subset of feedback informationassociated with the second new acknowledgment feedback indicator in thefirst group-based acknowledgment feedback. In some examples, thefeedback determination manager 1115 may concatenate the first subset offeedback information and the second subset of feedback information inthe first group-based acknowledgment feedback.

In some examples, the feedback determination manager 1115 may identify afirst codebook entry associated with the first subset of feedbackinformation. In some examples, the feedback determination manager 1115may identify a second codebook entry associated with the second subsetof feedback information.

In some examples, the feedback determination manager 1115 may transmit,to the base station, the first group-based acknowledgment feedback inthe first uplink transmission based on the first codebook entry and thesecond codebook entry.

In some examples, the feedback determination manager 1115 may update thesecond group-based acknowledgement feedback associated with the secondgroup of downlink transmissions based on the second downlink assignmentindicator and the second new acknowledgment feedback indicator fortransmission of a second group-based acknowledgement feedbacktransmission associated with the second group of downlink transmissions.

In some examples, the feedback determination manager 1115 may generate anegative acknowledgment for each downlink assignment indicatorassociated with the second group of downlink transmissions up to thesecond downlink assignment indicator, where a previous downlinkassignment indicator value for the second group of downlinktransmissions prior to the second downlink assignment indicator isdiscarded.

In some examples, the feedback determination manager 1115 may identifyone or more gaps between the second downlink assignment indicator and aprevious downlink assignment indicator value associated with the secondgroup of downlink transmissions provided with the prior downlink controlinformation transmission from the base station. In some examples, thefeedback determination manager 1115 may generate a negativeacknowledgment for each downlink assignment indicator associated withthe one or more gaps.

In some examples, the feedback determination manager 1115 may determinesecond acknowledgment feedback associated with the second group ofdownlink transmissions for inclusion with the first group-basedacknowledgement feedback transmission.

In some examples, the feedback determination manager 1115 may determine,based on the second group of downlink transmissions having a same newacknowledgment feedback indicator value as a prior downlink controlinformation transmission, second acknowledgment feedback associated withthe second group of downlink transmissions for inclusion with the firstgroup-based acknowledgement feedback transmission.

In some examples, the feedback determination manager 1115 may determinethe first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions and the second group-basedacknowledgment feedback associated with the second group of downlinktransmissions.

In some examples, the feedback determination manager 1115 may format thefirst group-based acknowledgment feedback and the second group-basedacknowledgment feedback into a combined feedback report. In someexamples, the feedback determination manager 1115 may append the secondgroup-based acknowledgment feedback to the first group-basedacknowledgment feedback based on a first group index of the firstgroup-based acknowledgment feedback having a lower index value than asecond group index of the second group-based acknowledgment feedback. Insome examples, the feedback determination manager 1115 may append thesecond group-based acknowledgment feedback to the first group-basedacknowledgment feedback based on a request for the second group-basedacknowledgment feedback being received in downlink control informationassociated with the first group of transmissions.

In some examples, the feedback determination manager 1115 may format thefirst acknowledgment feedback for one or more downlink transmissionsassociated with the first downlink control information format separatelyfrom second acknowledgment feedback associated with a different downlinkcontrol information having the second downlink control informationformat. In some cases, the first group-based acknowledgment feedback isformatted relative to a prior group-based acknowledgment feedback basedon whether the first new acknowledgment feedback indicator is differentthan a prior new acknowledgment feedback indicator associated with theprior group-based acknowledgment feedback. In some cases, a subsequentgroup-based acknowledgment feedback is formatted relative to the firstgroup-based acknowledgment feedback based on whether a subsequent newacknowledgment feedback indicator is different than the second newacknowledgment feedback indicator. In some cases, the first group-basedacknowledgment feedback is formatted based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time. In somecases, the first group-based acknowledgment feedback is formatted basedon which of the first new acknowledgment feedback indicator or thesecond new acknowledgment feedback indicator is received in a majorityof sets of group-based acknowledgment feedback parameters associatedwith the first group-based acknowledgment feedback.

In some cases, a downlink assignment indicator field is reset uponreceipt of a changed new acknowledgment feedback indicator value, andwhere different subsets of feedback information are determined for eachreset of the downlink assignment indicator field. In some cases, adownlink assignment indicator field is not reset within anacknowledgment/negative-acknowledgment opportunity.

In some cases, a downlink assignment indicator field of the seconddownlink control information format is applied separately whendetermining the second acknowledgment feedback.

In some cases, the first acknowledgment feedback includes feedbackinformation only for downlink transmissions associated with only thefirst downlink control information format or only the second downlinkcontrol information format. In some cases, the first acknowledgmentfeedback includes feedback information for downlink transmissionsassociated with both the first downlink control information format andthe second downlink control information format. In some cases, the firstacknowledgment feedback includes feedback information based on one ormore of a first codebook for downlink transmissions associated with thesecond downlink control information format, a second codebook fordownlink transmissions associated with the second downlink controlinformation format having a first group identification, or a thirdcodebook for downlink transmissions associated with the second downlinkcontrol information format having a second group identification.

The feedback transmission manager 1125 may transmit the firstgroup-based acknowledgement feedback transmission to the base station.In some examples, the feedback transmission manager 1125 may transmitonly a latest subset of feedback information associated with a latestreceived new acknowledgment feedback indicator. In some examples, thefeedback transmission manager 1125 may transmit the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback to the base station in the first uplink transmission. In someexamples, the feedback transmission manager 1125 may transmit thecombined feedback report to the base station in the first uplinktransmission.

In some cases, the feedback transmission manager 1125 may transmitnon-group-based acknowledgment feedback associated with the secondnon-group-based downlink transmission in the second acknowledgmentfeedback occasion. In some examples, the feedback transmission manager1125 may transmit group-based acknowledgment feedback associated withone or more or the first group-based downlink transmission or the thirdgroup-based downlink transmission in the third acknowledgment feedbackoccasion.

The downlink transmission manager 1130 may receive the one or moredownlink transmissions of the first group of downlink transmissions. Insome examples, the downlink transmission manager 1130 may receive one ormore downlink transmissions of the second group of downlinktransmissions. In some cases, the downlink transmission(s) of the secondgroup of downlink transmissions may be received prior to the one or moredownlink transmissions of the first group, and a DCI scheduling the oneor more downlink transmissions of the first group of downlinktransmissions may also request feedback for second group of downlinktransmissions.

In some cases, the downlink transmission manager 1130 may receive afirst downlink control information transmission from a base station thatis associated with a first group-based downlink transmission and a firstacknowledgment feedback occasion. In some examples, the downlinktransmission manager 1130 may receive a second downlink controlinformation transmission, subsequent to the first downlink controlinformation transmission, that is associated with a secondnon-group-based downlink transmission and a second acknowledgmentfeedback occasion. In some examples, the downlink transmission manager1130 may receive a third downlink control information transmission,subsequent to the second downlink control information transmission, thatis associated with a third group-based downlink transmission and a thirdacknowledgment feedback occasion.

The group determination manager 1120 may determine none of the first setof group-based acknowledgment feedback parameters or the second set ofgroup-based acknowledgment feedback parameters include an explicitindication that requests feedback of another group of downlinktransmissions. In some examples, the group determination manager 1120may determine that both the first feedback timing the second feedbacktiming indicate a same uplink transmission slot.

In some examples, the group determination manager 1120 may identify afirst request field value in the first set of group-based acknowledgmentfeedback parameters that indicates a request for only the first group ofdownlink transmissions, and a second request field value in a subsequentdownlink control information transmission associated with the firstgroup of downlink transmissions that indicates a request for both thefirst group of downlink transmissions and the second group of downlinktransmissions.

In some examples, the group determination manager 1120 may determinethat the first uplink transmission is to include both the firstgroup-based acknowledgement feedback and the second group-basedacknowledgment feedback based on the second request field value. In someexamples, the group determination manager 1120 when an initial receivedrequest field value indicates that the first uplink transmission is toinclude both the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback, and a subsequent receivedrequest field value indicates that only one of the first group-basedacknowledgement feedback or the second group-based acknowledgmentfeedback is to be provided with the first uplink transmission,discontinue group-based acknowledgment feedback determination for thefirst uplink transmission.

In some cases, the first downlink control information and the seconddownlink control information each further include a group indicator thatindicates that both the first downlink transmission and the seconddownlink transmission are in a same group of downlink transmissions.

In some cases, a latest received request field value is used todetermine whether the first uplink transmission includes both the firstgroup-based acknowledgement feedback and the second group-basedacknowledgment feedback.

In some cases, the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback may be transmitted when atleast one of the first downlink control information or the seconddownlink control information indicate a request for both the first groupof downlink transmissions and the second group of downlinktransmissions.

In some cases, the UE is not expected to receive different downlinkcontrol information transmissions that schedule downlink transmissionsof different downlink transmission groups and point to a sametransmission time for the first group-based acknowledgement feedback andthe second group-based acknowledgment feedback.

The NFI determination component 1135 may determine that a value of thesecond new acknowledgment feedback indicator is different than a priorvalue of the second new acknowledgement feedback indicator associatedwith the second group of downlink transmissions from a prior downlinkcontrol information transmission from the base station.

In some examples, the NFI determination component 1135 may determinethat a value of the second new acknowledgment feedback indicator isunchanged from a prior value of the second new acknowledgement feedbackindicator associated with the second group of downlink transmissionsfrom a prior downlink control information transmission from the basestation.

In some cases, the NFI determination component 1135 may determine thatan NFI is toggled between the first acknowledgment feedback occasion andthe third acknowledgment feedback occasion based on a difference in afirst NFI value provided in the first downlink control information and asecond NFI value provided in the third downlink control information. Insome cases, NFI is assumed to be toggled between the firstacknowledgment feedback occasion and the third acknowledgment feedbackoccasion.

FIG. 12 shows a diagram of a system 1200 including a device 1205 thatsupports group-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1205 may be an example of or include the components of device905, device 1005, or a UE 115 as described herein. The device 1205 mayinclude components for bi-directional voice and data communicationsincluding components for transmitting and receiving communications,including a communications manager 1210, an I/O controller 1215, atransceiver 1220, an antenna 1225, memory 1230, and a processor 1240.These components may be in electronic communication via one or morebuses (e.g., bus 1245).

The communications manager 1210 may receive a first downlink controlinformation transmission from a base station that provides a first setof group-based acknowledgment feedback parameters associated with afirst downlink transmission, where the first set of group-basedacknowledgment feedback parameters includes a first new acknowledgmentfeedback indicator and a first feedback timing that indicates a firstuplink transmission that is to include a first group-basedacknowledgment feedback, receive a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters associated with a seconddownlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, and determine, based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time, the firstgroup-based acknowledgment feedback.

The communications manager 1210 may also receive a downlink controlinformation transmission from a base station that provides a set ofgroup-based acknowledgment feedback parameters, where the set ofgroup-based acknowledgment feedback parameters includes a groupindicator that identifies at least a first group of downlinktransmissions to be included in a first group-based acknowledgementfeedback transmission, a first downlink assignment indicator thatidentifies one or more downlink transmissions of the first group ofdownlink transmissions, a second downlink assignment indicator thatidentifies one or more downlink transmissions of a second group ofdownlink transmissions, a first new acknowledgment feedback indicatorthat identifies whether the first downlink assignment indicator isreset, and a second new acknowledgment feedback indicator associatedwith the second group of downlink transmissions, receive the one or moredownlink transmissions of the first group of downlink transmissions,determine, based on the first downlink assignment indicator and thefirst new acknowledgment feedback indicator, first acknowledgmentfeedback associated with the first group of downlink transmissions forinclusion with the first group-based acknowledgement feedbacktransmission, update the second group-based acknowledgement feedbackassociated with the second group of downlink transmissions based on thedetermining and transmit the first group-based acknowledgement feedbacktransmission to the base station.

The communications manager 1210 may also receive a first downlinkcontrol information transmission from a base station that provides afirst set of group-based acknowledgment feedback parameters, where thefirst set of group-based acknowledgment feedback parameters includes afirst group indicator for a first group of downlink transmissions, and afirst feedback timing that indicates a first uplink transmission is toinclude a first group-based acknowledgment feedback associated with thefirst group of downlink transmissions, receive a second downlink controlinformation transmission from the base station that provides a secondset of group-based acknowledgment feedback parameters, where the secondset of group-based acknowledgment feedback parameters includes a secondgroup indicator for a second group of downlink transmissions, and asecond feedback timing that indicates the first uplink transmission isto include one or more of the first group-based acknowledgement feedbackor a second group-based acknowledgment feedback associated with thesecond group of downlink transmissions, and determine, based on thefirst feedback timing and the second feedback timing, that the firstuplink transmission is to include both the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.

The communications manager 1210 may also receive, from a base station,configuration information for group-based acknowledgment feedback forone or more groups of downlink transmissions to the UE, where one ormore parameters associated with the group-based acknowledgment feedbackare indicated in a first set of fields of a first downlink controlinformation format, and are absent from a second set of fields of asecond downlink control information format that is different than thefirst set of fields, where the first set of fields includes a firstsubset of information fields that are in addition to the second set offields, receive a downlink control information transmission from thebase station having the second downlink control information format,determine, based on using a predetermined value for each field of thefirst subset of information fields, first acknowledgment feedbackassociated with at least a first group of downlink transmissions, andtransmit the first acknowledgment feedback to the base station.

The communications manager 1210 may also receive a first downlinkcontrol information transmission from a base station that is associatedwith a first group-based downlink transmission and a firstacknowledgment feedback occasion, receive a second downlink controlinformation transmission, subsequent to the first downlink controlinformation transmission, that is associated with a secondnon-group-based downlink transmission and a second acknowledgmentfeedback occasion, receive a third downlink control informationtransmission, subsequent to the second downlink control informationtransmission, that is associated with a third group-based downlinktransmission and a third acknowledgment feedback occasion, transmitnon-group-based acknowledgment feedback associated with the secondnon-group-based downlink transmission in the second acknowledgmentfeedback occasion, and transmit group-based acknowledgment feedbackassociated with one or more or the first group-based downlinktransmission or the third group-based downlink transmission in the thirdacknowledgment feedback occasion.

The I/O controller 1215 may manage input and output signals for thedevice 1205. The I/O controller 1215 may also manage peripherals notintegrated into the device 1205. In some cases, the I/O controller 1215may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 1215 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 1215may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 1215may be implemented as part of a processor. In some cases, a user mayinteract with the device 1205 via the I/O controller 1215 or viahardware components controlled by the I/O controller 1215.

The transceiver 1220 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1220 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1220 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1225.However, in some cases the device may have more than one antenna 1225,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1230 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 1230 may store computer-readable,computer-executable code 1235 including instructions that, whenexecuted, cause the processor to perform various functions describedherein. In some cases, the memory 1230 may contain, among other things,a basic input/basic output system (BIOS) which may control basichardware or software operation such as the interaction with peripheralcomponents or devices.

The processor 1240 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1240 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 1240. The processor 1240 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 1230) to cause the device 1205 to perform variousfunctions (e.g., functions or tasks supporting group-basedacknowledgment feedback techniques for wireless communications).

The code 1235 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1235 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1235 may not be directly executable by theprocessor 1240 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 13 shows a block diagram 1300 of a device 1305 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1305 may be an example of aspects of a base station 105 asdescribed herein. The device 1305 may include a receiver 1310, acommunications manager 1315, and a transmitter 1320. The device 1305 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1310 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to group-basedacknowledgment feedback techniques for wireless communications, etc.).Information may be passed on to other components of the device 1305. Thereceiver 1310 may be an example of aspects of the transceiver 1620described with reference to FIG. 16. The receiver 1310 may utilize asingle antenna or a set of antennas.

The communications manager 1315 may transmit first downlink controlinformation to a UE that provides a first set of group-basedacknowledgment feedback parameters associated with a first downlinktransmission, where the first set of group-based acknowledgment feedbackparameters includes a first new acknowledgment feedback indicator and afirst feedback timing that indicates a first uplink transmission that isto include a first group-based acknowledgment feedback, transmit seconddownlink control information to the UE that provides a second set ofgroup-based acknowledgment feedback parameters associated with a seconddownlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, transmit the first downlink transmission andthe second downlink transmission to the UE, receive at least the firstgroup-based acknowledgment feedback from the UE in the first uplinktransmission.

The communications manager 1315 may also transmit downlink controlinformation to a UE that provides a set of group-based acknowledgmentfeedback parameters, where the set of group-based acknowledgmentfeedback parameters includes a group indicator that identifies at leasta first group of downlink transmissions to be included in a firstgroup-based acknowledgement feedback transmission, a first downlinkassignment indicator that identifies one or more downlink transmissionsof the first group of downlink transmissions, a second downlinkassignment indicator that identifies one or more downlink transmissionsof a second group of downlink transmissions, a first new acknowledgmentfeedback indicator that identifies whether the first downlink assignmentindicator is reset, and a second new acknowledgment feedback indicatorassociated with the second group of downlink transmissions, determine,based on the first downlink assignment indicator and the first newacknowledgment feedback indicator, which acknowledgment feedback is tobe included with the first group-based acknowledgement feedbacktransmission, transmit the one or more downlink transmissions of thefirst group of downlink transmissions to the UE, receive the firstgroup-based acknowledgement feedback transmission from the UE.

The communications manager 1315 may also transmit first downlink controlinformation to a UE that provides a first set of group-basedacknowledgment feedback parameters, where the first set of group-basedacknowledgment feedback parameters includes a first group indicator fora first group of downlink transmissions, and a first feedback timingthat indicates a first uplink transmission is to include a firstgroup-based acknowledgment feedback associated with the first group ofdownlink transmissions, transmit a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters, where the second set ofgroup-based acknowledgment feedback parameters includes a second groupindicator for a second group of downlink transmissions, and a secondfeedback timing that indicates the first uplink transmission is toinclude one or more of the first group-based acknowledgement feedback ora second group-based acknowledgment feedback associated with the secondgroup of downlink transmissions, and determine, based on the firstfeedback timing and the second feedback timing, whether the first uplinktransmission is to include one or more of the first group-basedacknowledgement feedback or the second group-based acknowledgmentfeedback.

The communications manager 1315 may also transmit, to a UE,configuration information for group-based acknowledgment feedback forone or more groups of downlink transmissions to the UE, where one ormore parameters associated with the group-based acknowledgment feedbackare indicated in a first set of fields of a first downlink controlinformation format, and are indicated in a second set of fields of asecond downlink control information format that is different than thefirst set of fields, transmit a downlink control informationtransmission from the base station having the second downlink controlinformation format, determine, based on the one or more parameters ofthe second set of fields of the second downlink control informationformat, that first acknowledgment feedback associated with at least afirst group of downlink transmissions is to be transmitted in the firstacknowledgment feedback, and receive the first acknowledgment feedbackfrom the UE. The communications manager 1315 may be an example ofaspects of the communications manager 1610 described herein.

The communications manager 1315, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 1315, or itssub-components may be executed by a general-purpose processor, a DSP, anapplication-specific integrated circuit (ASIC), a FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described in the present disclosure.

The communications manager 1315, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, thecommunications manager 1315, or its sub-components, may be a separateand distinct component in accordance with various aspects of the presentdisclosure. In some examples, the communications manager 1315, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with various aspects of the presentdisclosure.

The transmitter 1320 may transmit signals generated by other componentsof the device 1305. In some examples, the transmitter 1320 may becollocated with a receiver 1310 in a transceiver module. For example,the transmitter 1320 may be an example of aspects of the transceiver1620 described with reference to FIG. 16. The transmitter 1320 mayutilize a single antenna or a set of antennas.

FIG. 14 shows a block diagram 1400 of a device 1405 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1405 may be an example of aspects of a device 1305, or a basestation 105 as described herein. The device 1405 may include a receiver1410, a communications manager 1415, and a transmitter 1435. The device1405 may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1410 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to group-basedacknowledgment feedback techniques for wireless communications, etc.).Information may be passed on to other components of the device 1405. Thereceiver 1410 may be an example of aspects of the transceiver 1620described with reference to FIG. 16. The receiver 1410 may utilize asingle antenna or a set of antennas.

The communications manager 1415 may be an example of aspects of thecommunications manager 1315 as described herein. The communicationsmanager 1415 may include a group-based feedback manager 1420, a downlinktransmission manager 1425, and a feedback determination manager 1430.The communications manager 1415 may be an example of aspects of thecommunications manager 1610 described herein.

In some cases, the group-based feedback manager 1420 may transmit firstdownlink control information to a UE that provides a first set ofgroup-based acknowledgment feedback parameters associated with a firstdownlink transmission, where the first set of group-based acknowledgmentfeedback parameters includes a first new acknowledgment feedbackindicator and a first feedback timing that indicates a first uplinktransmission that is to include a first group-based acknowledgmentfeedback and transmit second downlink control information to the UE thatprovides a second set of group-based acknowledgment feedback parametersassociated with a second downlink transmission, where the second set ofgroup-based acknowledgment feedback parameters includes a second newacknowledgment feedback indicator that is different than the first newacknowledgment feedback indicator, and a second feedback timing thatindicates the first uplink transmission is to include the firstgroup-based acknowledgment feedback. The downlink transmission manager1425 may transmit the first downlink transmission and the seconddownlink transmission to the UE. The feedback determination manager 1430may receive at least the first group-based acknowledgment feedback fromthe UE in the first uplink transmission.

In some cases, the group-based feedback manager 1420 may transmitdownlink control information to a UE that provides a set of group-basedacknowledgment feedback parameters, where the set of group-basedacknowledgment feedback parameters includes a group indicator thatidentifies at least a first group of downlink transmissions to beincluded in a first group-based acknowledgement feedback transmission, afirst downlink assignment indicator that identifies one or more downlinktransmissions of the first group of downlink transmissions, a seconddownlink assignment indicator that identifies one or more downlinktransmissions of a second group of downlink transmissions, a first newacknowledgment feedback indicator that identifies whether the firstdownlink assignment indicator is reset, and a second new acknowledgmentfeedback indicator associated with the second group of downlinktransmissions and determine, based on the first downlink assignmentindicator and the first new acknowledgment feedback indicator, whichacknowledgment feedback is to be included with the first group-basedacknowledgement feedback transmission. The downlink transmission manager1425 may transmit the one or more downlink transmissions of the firstgroup of downlink transmissions to the UE. The feedback determinationmanager 1430 may receive the first group-based acknowledgement feedbacktransmission from the UE.

In some cases, the group-based feedback manager 1420 may transmit firstdownlink control information to a UE that provides a first set ofgroup-based acknowledgment feedback parameters, where the first set ofgroup-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions and transmit a second downlink controlinformation transmission from the base station that provides a secondset of group-based acknowledgment feedback parameters, where the secondset of group-based acknowledgment feedback parameters includes a secondgroup indicator for a second group of downlink transmissions, and asecond feedback timing that indicates the first uplink transmission isto include one or more of the first group-based acknowledgement feedbackor a second group-based acknowledgment feedback associated with thesecond group of downlink transmissions. The feedback determinationmanager 1430 may determine, based on the first feedback timing and thesecond feedback timing, whether the first uplink transmission is toinclude one or more of the first group-based acknowledgement feedback orthe second group-based acknowledgment feedback.

In some cases, the group-based feedback manager 1420 may transmit, to aUE, configuration information for group-based acknowledgment feedbackfor one or more groups of downlink transmissions to the UE, where one ormore parameters associated with the group-based acknowledgment feedbackare indicated in a first set of fields of a first downlink controlinformation format, and are indicated in a second set of fields of asecond downlink control information format that is different than thefirst set of fields and transmit a downlink control informationtransmission from the base station having the second downlink controlinformation format. The feedback determination manager 1430 maydetermine, based on the one or more parameters of the second set offields of the second downlink control information format, that firstacknowledgment feedback associated with at least a first group ofdownlink transmissions is to be transmitted in the first acknowledgmentfeedback and receive the first acknowledgment feedback from the UE.

The transmitter 1435 may transmit signals generated by other componentsof the device 1405. In some examples, the transmitter 1435 may becollocated with a receiver 1410 in a transceiver module. For example,the transmitter 1435 may be an example of aspects of the transceiver1620 described with reference to FIG. 16. The transmitter 1435 mayutilize a single antenna or a set of antennas.

FIG. 15 shows a block diagram 1500 of a communications manager 1505 thatsupports group-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Thecommunications manager 1505 may be an example of aspects of acommunications manager 1315, a communications manager 1415, or acommunications manager 1610 described herein. The communications manager1505 may include a group-based feedback manager 1510, a downlinktransmission manager 1515, a feedback determination manager 1520, and agroup determination manager 1525. Each of these modules may communicate,directly or indirectly, with one another (e.g., via one or more buses).

The group-based feedback manager 1510 may transmit first downlinkcontrol information to a UE that provides a first set of group-basedacknowledgment feedback parameters associated with a first downlinktransmission, where the first set of group-based acknowledgment feedbackparameters includes a first new acknowledgment feedback indicator and afirst feedback timing that indicates a first uplink transmission that isto include a first group-based acknowledgment feedback.

In some examples, the group-based feedback manager 1510 may transmitsecond downlink control information to the UE that provides a second setof group-based acknowledgment feedback parameters associated with asecond downlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback.

In some examples, the group-based feedback manager 1510 may transmitdownlink control information to a UE that provides a set of group-basedacknowledgment feedback parameters, where the set of group-basedacknowledgment feedback parameters includes a group indicator thatidentifies at least a first group of downlink transmissions to beincluded in a first group-based acknowledgement feedback transmission, afirst downlink assignment indicator that identifies one or more downlinktransmissions of the first group of downlink transmissions, a seconddownlink assignment indicator that identifies one or more downlinktransmissions of a second group of downlink transmissions, a first newacknowledgment feedback indicator that identifies whether the firstdownlink assignment indicator is reset, and a second new acknowledgmentfeedback indicator associated with the second group of downlinktransmissions.

In some examples, the group-based feedback manager 1510 may determine,based on the first downlink assignment indicator and the first newacknowledgment feedback indicator, which acknowledgment feedback is tobe included with the first group-based acknowledgement feedbacktransmission.

In some examples, the group-based feedback manager 1510 may transmitfirst downlink control information to a UE that provides a first set ofgroup-based acknowledgment feedback parameters, where the first set ofgroup-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions.

In some examples, the group-based feedback manager 1510 may transmit asecond downlink control information transmission from the base stationthat provides a second set of group-based acknowledgment feedbackparameters, where the second set of group-based acknowledgment feedbackparameters includes a second group indicator for a second group ofdownlink transmissions, and a second feedback timing that indicates thefirst uplink transmission is to include one or more of the firstgroup-based acknowledgement feedback or a second group-basedacknowledgment feedback associated with the second group of downlinktransmissions.

In some examples, the group-based feedback manager 1510 may transmit, toa UE, configuration information for group-based acknowledgment feedbackfor one or more groups of downlink transmissions to the UE, where one ormore parameters associated with the group-based acknowledgment feedbackare indicated in a first set of fields of a first downlink controlinformation format, and are indicated in a second set of fields of asecond downlink control information format that is different than thefirst set of fields.

In some examples, the group-based feedback manager 1510 may transmit adownlink control information transmission from the base station havingthe second downlink control information format.

The downlink transmission manager 1515 may transmit the first downlinktransmission and the second downlink transmission to the UE. In someexamples, the downlink transmission manager 1515 may transmit the one ormore downlink transmissions of the first group of downlink transmissionsto the UE.

The feedback determination manager 1520 may receive at least the firstgroup-based acknowledgment feedback from the UE in the first uplinktransmission. In some examples, the feedback determination manager 1520may receive the first group-based acknowledgement feedback transmissionfrom the UE. In some examples, the feedback determination manager 1520may determine, based on the first feedback timing and the secondfeedback timing, whether the first uplink transmission is to include oneor more of the first group-based acknowledgement feedback or the secondgroup-based acknowledgment feedback. In some examples, the feedbackdetermination manager 1520 may determine, based on the one or moreparameters of the second set of fields of the second downlink controlinformation format, that first acknowledgment feedback associated withat least a first group of downlink transmissions is to be transmitted inthe first acknowledgment feedback. In some examples, the feedbackdetermination manager 1520 may receive the first acknowledgment feedbackfrom the UE.

The group determination manager 1525 may determine one or more groups ofdownlink transmissions. In some cases, the first set of group-basedacknowledgment feedback parameters and the second set of group-basedacknowledgment feedback parameters do not include an explicit indicationthat requests feedback of another group of downlink transmissions.

FIG. 16 shows a diagram of a system 1600 including a device 1605 thatsupports group-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1605 may be an example of or include the components of device1305, device 1405, or a base station 105 as described herein. The device1605 may include components for bi-directional voice and datacommunications including components for transmitting and receivingcommunications, including a communications manager 1610, a networkcommunications manager 1615, a transceiver 1620, an antenna 1625, memory1630, a processor 1640, and an inter-station communications manager1645. These components may be in electronic communication via one ormore buses (e.g., bus 1650).

The communications manager 1610 may transmit first downlink controlinformation to a UE that provides a first set of group-basedacknowledgment feedback parameters associated with a first downlinktransmission, where the first set of group-based acknowledgment feedbackparameters includes a first new acknowledgment feedback indicator and afirst feedback timing that indicates a first uplink transmission that isto include a first group-based acknowledgment feedback, transmit seconddownlink control information to the UE that provides a second set ofgroup-based acknowledgment feedback parameters associated with a seconddownlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback, transmit the first downlink transmission andthe second downlink transmission to the UE, receive at least the firstgroup-based acknowledgment feedback from the UE in the first uplinktransmission.

The communications manager 1610 may also transmit downlink controlinformation to a UE that provides a set of group-based acknowledgmentfeedback parameters, where the set of group-based acknowledgmentfeedback parameters includes a group indicator that identifies at leasta first group of downlink transmissions to be included in a firstgroup-based acknowledgement feedback transmission, a first downlinkassignment indicator that identifies one or more downlink transmissionsof the first group of downlink transmissions, a second downlinkassignment indicator that identifies one or more downlink transmissionsof a second group of downlink transmissions, a first new acknowledgmentfeedback indicator that identifies whether the first downlink assignmentindicator is reset, and a second new acknowledgment feedback indicatorassociated with the second group of downlink transmissions, determine,based on the first downlink assignment indicator and the first newacknowledgment feedback indicator, which acknowledgment feedback is tobe included with the first group-based acknowledgement feedbacktransmission, transmit the one or more downlink transmissions of thefirst group of downlink transmissions to the UE, receive the firstgroup-based acknowledgement feedback transmission from the UE.

The communications manager 1610 may also transmit first downlink controlinformation to a UE that provides a first set of group-basedacknowledgment feedback parameters, where the first set of group-basedacknowledgment feedback parameters includes a first group indicator fora first group of downlink transmissions, and a first feedback timingthat indicates a first uplink transmission is to include a firstgroup-based acknowledgment feedback associated with the first group ofdownlink transmissions, transmit a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters, where the second set ofgroup-based acknowledgment feedback parameters includes a second groupindicator for a second group of downlink transmissions, and a secondfeedback timing that indicates the first uplink transmission is toinclude one or more of the first group-based acknowledgement feedback ora second group-based acknowledgment feedback associated with the secondgroup of downlink transmissions, and determine, based on the firstfeedback timing and the second feedback timing, whether the first uplinktransmission is to include one or more of the first group-basedacknowledgement feedback or the second group-based acknowledgmentfeedback.

The communications manager 1610 may also transmit, to a UE,configuration information for group-based acknowledgment feedback forone or more groups of downlink transmissions to the UE, where one ormore parameters associated with the group-based acknowledgment feedbackare indicated in a first set of fields of a first downlink controlinformation format, and are indicated in a second set of fields of asecond downlink control information format that is different than thefirst set of fields, transmit a downlink control informationtransmission from the base station having the second downlink controlinformation format, determine, based on the one or more parameters ofthe second set of fields of the second downlink control informationformat, that first acknowledgment feedback associated with at least afirst group of downlink transmissions is to be transmitted in the firstacknowledgment feedback, and receive the first acknowledgment feedbackfrom the UE.

The network communications manager 1615 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1615 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1620 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1620 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1620 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1625.However, in some cases the device may have more than one antenna 1625,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1630 may include RAM, ROM, or a combination thereof. Thememory 1630 may store computer-readable code 1635 including instructionsthat, when executed by a processor (e.g., the processor 1640) cause thedevice to perform various functions described herein. In some cases, thememory 1630 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1640 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1640 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 1640. The processor 1640 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 1630) to cause the device 1605 to perform various functions(e.g., functions or tasks supporting group-based acknowledgment feedbacktechniques for wireless communications).

The inter-station communications manager 1645 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager1645 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1645 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

The code 1635 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1635 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1635 may not be directly executable by theprocessor 1640 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 17 shows a flowchart illustrating a method 1700 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 1700 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method1700 may be performed by a communications manager as described withreference to FIGS. 9 through 12. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1705, the UE may receive a first downlink control informationtransmission from a base station that provides a first set ofgroup-based acknowledgment feedback parameters associated with a firstdownlink transmission, where the first set of group-based acknowledgmentfeedback parameters includes a first new acknowledgment feedbackindicator and a first feedback timing that indicates a first uplinktransmission that is to include a first group-based acknowledgmentfeedback. The operations of 1705 may be performed according to themethods described herein. In some examples, aspects of the operations of1705 may be performed by a group-based feedback manager as describedwith reference to FIGS. 9 through 12.

At 1710, the UE may receive a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters associated with a seconddownlink transmission, where the second set of group-basedacknowledgment feedback parameters includes a second new acknowledgmentfeedback indicator that is different than the first new acknowledgmentfeedback indicator, and a second feedback timing that indicates thefirst uplink transmission is to include the first group-basedacknowledgment feedback. The operations of 1710 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1710 may be performed by a group-based feedbackmanager as described with reference to FIGS. 9 through 12.

At 1715, the UE may determine, based on which of the first newacknowledgment feedback indicator or the second new acknowledgmentfeedback indicator is received earliest or latest in time, the firstgroup-based acknowledgment feedback. The operations of 1715 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1715 may be performed by a feedbackdetermination manager as described with reference to FIGS. 9 through 12.

FIG. 18 shows a flowchart illustrating a method 1800 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 1800 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method1800 may be performed by a communications manager as described withreference to FIGS. 9 through 12. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1805, the UE may receive a downlink control information transmissionfrom a base station that provides a set of group-based acknowledgmentfeedback parameters, where the set of group-based acknowledgmentfeedback parameters includes a group indicator that identifies at leasta first group of downlink transmissions to be included in a firstgroup-based acknowledgement feedback transmission, a first downlinkassignment indicator that identifies one or more downlink transmissionsof the first group of downlink transmissions, a second downlinkassignment indicator that identifies one or more downlink transmissionsof a second group of downlink transmissions, a first new acknowledgmentfeedback indicator that identifies whether the first downlink assignmentindicator is reset, and a second new acknowledgment feedback indicatorassociated with the second group of downlink transmissions. Theoperations of 1805 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1805 may beperformed by a group-based feedback manager as described with referenceto FIGS. 9 through 12.

At 1810, the UE may receive the one or more downlink transmissions ofthe first group of downlink transmissions. The operations of 1810 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1810 may be performed by a downlinktransmission manager as described with reference to FIGS. 9 through 12.

At 1815, the UE may determine, based on the first downlink assignmentindicator and the first new acknowledgment feedback indicator, firstacknowledgment feedback associated with the first group of downlinktransmissions for inclusion with the first group-based acknowledgementfeedback transmission. The operations of 1815 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 1815 may be performed by a feedback determination manageras described with reference to FIGS. 9 through 12.

At 1820, the UE may update the second group-based acknowledgementfeedback associated with the second group of downlink transmissionsbased on the determining. The operations of 1820 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1820 may be performed by a feedback transmissionmanager as described with reference to FIGS. 9 through 12.

At 1825, the UE may transmit the first group-based acknowledgementfeedback transmission to the base station. The operations of 1825 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1825 may be performed by a feedbacktransmission manager as described with reference to FIGS. 9 through 12.

FIG. 19 shows a flowchart illustrating a method 1900 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 1900 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method1900 may be performed by a communications manager as described withreference to FIGS. 9 through 12. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1905, the UE may receive a first downlink control informationtransmission from a base station that provides a first set ofgroup-based acknowledgment feedback parameters, where the first set ofgroup-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions. The operations of 1905 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1905 may be performed by a group-based feedbackmanager as described with reference to FIGS. 9 through 12.

At 1910, the UE may receive a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters, where the second set ofgroup-based acknowledgment feedback parameters includes a second groupindicator for a second group of downlink transmissions, and a secondfeedback timing that indicates the first uplink transmission is toinclude one or more of the first group-based acknowledgement feedback ora second group-based acknowledgment feedback associated with the secondgroup of downlink transmissions. The operations of 1910 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1910 may be performed by a group-based feedbackmanager as described with reference to FIGS. 9 through 12.

At 1915, the UE may determine, based on the first feedback timing andthe second feedback timing, that the first uplink transmission is toinclude both the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback. The operations of 1915 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1915 may be performed by afeedback determination manager as described with reference to FIGS. 9through 12.

FIG. 20 shows a flowchart illustrating a method 2000 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 2000 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method2000 may be performed by a communications manager as described withreference to FIGS. 9 through 12. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 2005, the UE may receive a first downlink control informationtransmission from a base station that provides a first set ofgroup-based acknowledgment feedback parameters, where the first set ofgroup-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions. The operations of 2005 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2005 may be performed by a group-based feedbackmanager as described with reference to FIGS. 9 through 12.

At 2010, the UE may receive a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters, where the second set ofgroup-based acknowledgment feedback parameters includes a second groupindicator for a second group of downlink transmissions, and a secondfeedback timing that indicates the first uplink transmission is toinclude one or more of the first group-based acknowledgement feedback ora second group-based acknowledgment feedback associated with the secondgroup of downlink transmissions. The operations of 2010 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2010 may be performed by a group-based feedbackmanager as described with reference to FIGS. 9 through 12.

At 2015, the UE may determine, based on the first feedback timing andthe second feedback timing, that the first uplink transmission is toinclude both the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback. The operations of 2015 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 2015 may be performed by afeedback determination manager as described with reference to FIGS. 9through 12.

At 2020, the UE may receive the one or more downlink transmissions ofthe first group of downlink transmissions and the second group ofdownlink transmissions. The operations of 2020 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2020 may be performed by a downlink transmissionmanager as described with reference to FIGS. 9 through 12.

At 2025, the UE may determine the first group-based acknowledgmentfeedback associated with the first group of downlink transmissions andthe second group-based acknowledgment feedback associated with thesecond group of downlink transmissions. The operations of 2025 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2025 may be performed by a feedbackdetermination manager as described with reference to FIGS. 9 through 12.

At 2030, the UE may transmit the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback to the basestation in the first uplink transmission. The operations of 2030 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2030 may be performed by a feedbacktransmission manager as described with reference to FIGS. 9 through 12.

FIG. 21 shows a flowchart illustrating a method 2100 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 2100 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method2100 may be performed by a communications manager as described withreference to FIGS. 9 through 12. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 2105, the UE may receive a first downlink control informationtransmission from a base station that provides a first set ofgroup-based acknowledgment feedback parameters, where the first set ofgroup-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions. The operations of 2105 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2105 may be performed by a group-based feedbackmanager as described with reference to FIGS. 9 through 12.

At 2110, the UE may receive a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters, where the second set ofgroup-based acknowledgment feedback parameters includes a second groupindicator for a second group of downlink transmissions, and a secondfeedback timing that indicates the first uplink transmission is toinclude one or more of the first group-based acknowledgement feedback ora second group-based acknowledgment feedback associated with the secondgroup of downlink transmissions. The operations of 2110 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2110 may be performed by a group-based feedbackmanager as described with reference to FIGS. 9 through 12.

At 2115, the UE may determine, based on the first feedback timing andthe second feedback timing, that the first uplink transmission is toinclude both the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback. The operations of 2115 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 2115 may be performed by afeedback determination manager as described with reference to FIGS. 9through 12.

At 2120, the UE may receive the one or more downlink transmissions ofthe first group of downlink transmissions and the second group ofdownlink transmissions. The operations of 2120 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2120 may be performed by a downlink transmissionmanager as described with reference to FIGS. 9 through 12.

At 2125, the UE may determine the first group-based acknowledgmentfeedback associated with the first group of downlink transmissions andthe second group-based acknowledgment feedback associated with thesecond group of downlink transmissions. The operations of 2125 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2125 may be performed by a feedbackdetermination manager as described with reference to FIGS. 9 through 12.

At 2130, the UE may format the first group-based acknowledgment feedbackand the second group-based acknowledgment feedback into a combinedfeedback report. The operations of 2130 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 2130 may be performed by a feedback determination manageras described with reference to FIGS. 9 through 12.

At 2135, the UE may transmit the combined feedback report to the basestation in the first uplink transmission. The operations of 2135 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2135 may be performed by a feedbacktransmission manager as described with reference to FIGS. 9 through 12.

FIG. 22 shows a flowchart illustrating a method 2200 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 2200 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method2200 may be performed by a communications manager as described withreference to FIGS. 9 through 12. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 2205, the UE may receive, from a base station, configurationinformation for group-based acknowledgment feedback for one or moregroups of downlink transmissions to the UE, where one or more parametersassociated with the group-based acknowledgment feedback are indicated ina first set of fields of a first downlink control information format,and are absent from a second set of fields of a second downlink controlinformation format that is different than the first set of fields, wherethe first set of fields includes a first subset of information fieldsthat are in addition to the second set of fields. The operations of 2205may be performed according to the methods described herein. In someexamples, aspects of the operations of 2205 may be performed by agroup-based feedback manager as described with reference to FIGS. 9through 12.

At 2210, the UE may receive a downlink control information transmissionfrom the base station having the second downlink control informationformat. The operations of 2210 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2210may be performed by a group-based feedback manager as described withreference to FIGS. 9 through 12.

At 2215, the UE may determine, based on using a predetermined value foreach field of the first subset of information fields, firstacknowledgment feedback associated with at least a first group ofdownlink transmissions. The operations of 2215 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2215 may be performed by a group-based feedbackmanager as described with reference to FIGS. 9 through 12.

At 2220, the UE may transmit the first acknowledgment feedback to thebase station. The operations of 2220 may be performed according to themethods described herein. In some examples, aspects of the operations of2220 may be performed by a feedback transmission manager as describedwith reference to FIGS. 9 through 12.

FIG. 23 shows a flowchart illustrating a method 2300 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 2300 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method2300 may be performed by a communications manager as described withreference to FIGS. 9 through 12. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 2305, the UE may receive a first downlink control informationtransmission from a base station that is associated with a firstgroup-based downlink transmission and a first acknowledgment feedbackoccasion. The operations of 2305 may be performed according to themethods described herein. In some examples, aspects of the operations of2305 may be performed by a downlink transmission manager as describedwith reference to FIGS. 9 through 12.

At 2310, the UE may receive a second downlink control informationtransmission, subsequent to the first downlink control informationtransmission, that is associated with a second non-group-based downlinktransmission and a second acknowledgment feedback occasion. Theoperations of 2310 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2310 may beperformed by a downlink transmission manager as described with referenceto FIGS. 9 through 12.

At 2315, the UE may transmit non-group-based acknowledgment feedbackassociated with the second non-group-based downlink transmission in thesecond acknowledgment feedback occasion. The operations of 2315 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2315 may be performed by a feedbacktransmission manager as described with reference to FIGS. 9 through 12.

At 2320, the UE may receive a third downlink control informationtransmission, subsequent to the second downlink control informationtransmission, that is associated with a third group-based downlinktransmission and a third acknowledgment feedback occasion. Theoperations of 2320 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2320 may beperformed by a downlink transmission manager as described with referenceto FIGS. 9 through 12.

At 2325, the UE may transmit group-based acknowledgment feedbackassociated with one or more or the first group-based downlinktransmission or the third group-based downlink transmission in the thirdacknowledgment feedback occasion. The operations of 2325 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2325 may be performed by a feedbacktransmission manager as described with reference to FIGS. 9 through 12.

FIG. 24 shows a flowchart illustrating a method 2400 that supportsgroup-based acknowledgment feedback techniques for wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 2400 may be implemented by a base station 105 orits components as described herein. For example, the operations ofmethod 2400 may be performed by a communications manager as describedwith reference to FIGS. 13 through 16. In some examples, a base stationmay execute a set of instructions to control the functional elements ofthe base station to perform the functions described below. Additionallyor alternatively, a base station may perform aspects of the functionsdescribed below using special-purpose hardware.

At 2405, the base station may transmit a first downlink controlinformation to a UE that provides a first set of group-basedacknowledgment feedback parameters associated with a first downlinktransmission, where the first set of group-based acknowledgment feedbackparameters includes a first new acknowledgment feedback indicator and afirst feedback timing that indicates a first uplink transmission that isto include a first group-based acknowledgment feedback. The operationsof 2405 may be performed according to the methods described herein. Insome examples, aspects of the operations of 2405 may be performed by adownlink transmission manager as described with reference to FIGS. 13through 16.

At 2410, the base station may transmit a second downlink controlinformation to the UE that provides a second set of group-basedacknowledgment feedback parameters associated with a second downlinktransmission, where the second set of group-based acknowledgmentfeedback parameters includes a second new acknowledgment feedbackindicator that is different than the first new acknowledgment feedbackindicator, and a second feedback timing that indicates the first uplinktransmission is to include the first group-based acknowledgmentfeedback. The operations of 2410 may be performed according to themethods described herein. In some examples, aspects of the operations of2410 may be performed by a downlink transmission manager as describedwith reference to FIGS. 13 through 16.

At 2415, the base station may transmit the first downlink transmissionand the second downlink transmission to the UE. The operations of 2415may be performed according to the methods described herein. In someexamples, aspects of the operations of 2415 may be performed by afeedback transmission manager as described with reference to FIGS. 13through 14.

At 2420, the base station may receive at least the first group-basedacknowledgment feedback from the UE in the first uplink transmission.The operations of 2420 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2420may be performed by a downlink transmission manager as described withreference to FIGS. 13 through 16.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.A CDMA system may implement a radio technology such as CDMA2000,Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,IS-95, and IS-856 standards. IS-2000 Releases may be commonly referredto as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned herein as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell maybe associated with a lower-powered base station, as compared with amacro cell, and a small cell may operate in the same or different (e.g.,licensed, unlicensed, etc.) frequency bands as macro cells. Small cellsmay include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs with service subscriptionswith the network provider. A femto cell may also cover a smallgeographic area (e.g., a home) and may provide restricted access by UEshaving an association with the femto cell (e.g., UEs in a closedsubscriber group (CSG), UEs for users in the home, and the like). An eNBfor a macro cell may be referred to as a macro eNB. An eNB for a smallcell may be referred to as a small cell eNB, a pico eNB, a femto eNB, ora home eNB. An eNB may support one or multiple (e.g., two, three, four,and the like) cells, and may also support communications using one ormultiple component carriers.

The wireless communications systems described herein may supportsynchronous or asynchronous operation. For synchronous operation, thebase stations may have similar frame timing, and transmissions fromdifferent base stations may be approximately aligned in time. Forasynchronous operation, the base stations may have different frametiming, and transmissions from different base stations may not bealigned in time. The techniques described herein may be used for eithersynchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA, or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices(e.g., a combination of a DSP and a microprocessor, multiplemicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communications at a userequipment (UE), comprising: receiving a first downlink controlinformation transmission from a base station that provides a first setof group-based acknowledgment feedback parameters, wherein the first setof group-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions; receiving a second downlink controlinformation transmission from the base station that provides a secondset of group-based acknowledgment feedback parameters, wherein thesecond set of group-based acknowledgment feedback parameters includes asecond group indicator for a second group of downlink transmissions, anda second feedback timing that indicates the first uplink transmission isto include one or more of the first group-based acknowledgement feedbackor a second group-based acknowledgment feedback associated with thesecond group of downlink transmissions; and determining, based at leastin part on the first feedback timing and the second feedback timing,that the first uplink transmission is to include both the firstgroup-based acknowledgement feedback and the second group-basedacknowledgment feedback.
 2. The method of claim 1, further comprising:receiving one or more downlink transmissions of the first group ofdownlink transmissions and the second group of downlink transmissions;determining the first group-based acknowledgment feedback associatedwith the first group of downlink transmissions and the secondgroup-based acknowledgment feedback associated with the second group ofdownlink transmissions; and transmitting the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback to the base station in the first uplink transmission.
 3. Themethod of claim 1, wherein none of the first set of group-basedacknowledgment feedback parameters or the second set of group-basedacknowledgment feedback parameters include an explicit indication thatrequests feedback of another group of downlink transmissions.
 4. Themethod of claim 3, wherein the determining further comprises:determining that both the first feedback timing the second feedbacktiming indicate a same uplink transmission slot.
 5. The method of claim1, wherein the determining further comprises: identifying a firstrequest field value in the first set of group-based acknowledgmentfeedback parameters that indicates a request for only the first group ofdownlink transmissions, and a second request field value in a subsequentdownlink control information transmission associated with the firstgroup of downlink transmissions that indicates a request for both thefirst group of downlink transmissions and the second group of downlinktransmissions; and determining that the first uplink transmission is toinclude both the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback based at least in part on thesecond request field value.
 6. The method of claim 5, wherein a latestreceived request field value is used to determine whether the firstuplink transmission includes both the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback.
 7. Themethod of claim 5, wherein the UE is not expected to receive differentdownlink control information transmissions that schedule downlinktransmissions of different downlink transmission groups and point to asame transmission time for the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback.
 8. Themethod of claim 5, wherein when an initial received request field valueindicates that the first uplink transmission is to include both thefirst group-based acknowledgement feedback and the second group-basedacknowledgment feedback, and a subsequent received request field valueindicates that only one of the first group-based acknowledgementfeedback or the second group-based acknowledgment feedback is to beprovided with the first uplink transmission, the UE discontinuesgroup-based acknowledgment feedback determination for the first uplinktransmission.
 9. The method of claim 5, wherein the UE transmits thefirst group-based acknowledgement feedback and the second group-basedacknowledgment feedback when at least one of the first set ofgroup-based acknowledgment feedback parameters or the second set ofgroup-based acknowledgment feedback parameters indicates a request forboth the first group of downlink transmissions and the second group ofdownlink transmissions.
 10. The method of claim 1, further comprising:receiving one or more downlink transmissions of the first group ofdownlink transmissions and the second group of downlink transmissions;determining the first group-based acknowledgment feedback associatedwith the first group of downlink transmissions and the secondgroup-based acknowledgment feedback associated with the second group ofdownlink transmissions; formatting the first group-based acknowledgmentfeedback and the second group-based acknowledgment feedback into acombined feedback report; and transmitting the combined feedback reportto the base station in the first uplink transmission.
 11. The method ofclaim 10, wherein the formatting comprises: appending the secondgroup-based acknowledgment feedback to the first group-basedacknowledgment feedback based at least in part on a first group index ofthe first group-based acknowledgment feedback having a lower index valuethan a second group index of the second group-based acknowledgmentfeedback.
 12. The method of claim 10, wherein the formatting comprises:appending the second group-based acknowledgment feedback to the firstgroup-based acknowledgment feedback based at least in part on a requestfor the second group-based acknowledgment feedback being received indownlink control information associated with the first group of downlinktransmissions.
 13. An apparatus for wireless communications at a userequipment (UE), comprising: a processor; memory coupled with theprocessor; and instructions stored in the memory and executable by theprocessor to cause the apparatus to: receive a first downlink controlinformation transmission from a base station that provides a first setof group-based acknowledgment feedback parameters, wherein the first setof group-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions; receive a second downlink controlinformation transmission from the base station that provides a secondset of group-based acknowledgment feedback parameters, wherein thesecond set of group-based acknowledgment feedback parameters includes asecond group indicator for a second group of downlink transmissions, anda second feedback timing that indicates the first uplink transmission isto include one or more of the first group-based acknowledgement feedbackor a second group-based acknowledgment feedback associated with thesecond group of downlink transmissions; and determine, based at least inpart on the first feedback timing and the second feedback timing, thatthe first uplink transmission is to include both the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.
 14. The apparatus of claim 13, wherein the instructions arefurther executable by the processor to cause the apparatus to: receiveone or more downlink transmissions of the first group of downlinktransmissions and the second group of downlink transmissions; determinethe first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions and the second group-basedacknowledgment feedback associated with the second group of downlinktransmissions; and transmit the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback to the basestation in the first uplink transmission.
 15. The apparatus of claim 13,wherein none of the first set of group-based acknowledgment feedbackparameters or the second set of group-based acknowledgment feedbackparameters include an explicit indication that requests feedback ofanother group of downlink transmissions.
 16. The apparatus of claim 15,wherein the instructions to determine are further executable by theprocessor to cause the apparatus to: determine that both the firstfeedback timing the second feedback timing indicate a same uplinktransmission slot.
 17. The apparatus of claim 13, wherein theinstructions to determine are further executable by the processor tocause the apparatus to: identify a first request field value in thefirst set of group-based acknowledgment feedback parameters thatindicates a request for only the first group of downlink transmissions,and a second request field value in a subsequent downlink controlinformation transmission associated with the first group of downlinktransmissions that indicates a request for both the first group ofdownlink transmissions and the second group of downlink transmissions;and determine that the first uplink transmission is to include both thefirst group-based acknowledgement feedback and the second group-basedacknowledgment feedback based at least in part on the second requestfield value.
 18. The apparatus of claim 17, wherein a latest receivedrequest field value is used to determine whether the first uplinktransmission includes both the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback.
 19. Theapparatus of claim 17, wherein the UE is not expected to receivedifferent downlink control information transmissions that scheduledownlink transmissions of different downlink transmission groups andpoint to a same transmission time for the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.
 20. The apparatus of claim 17, wherein when an initialreceived request field value indicates that the first uplinktransmission is to include both the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback, and asubsequent received request field value indicates that only one of thefirst group-based acknowledgement feedback or the second group-basedacknowledgment feedback is to be provided with the first uplinktransmission, the UE discontinues group-based acknowledgment feedbackdetermination for the first uplink transmission.
 21. The apparatus ofclaim 17, wherein the UE transmits the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback when atleast one of the first set of group-based acknowledgment feedbackparameters or the second set of group-based acknowledgment feedbackparameters indicates a request for both the first group of downlinktransmissions and the second group of downlink transmissions.
 22. Theapparatus of claim 13, wherein the instructions are further executableby the processor to cause the apparatus to: receive one or more downlinktransmissions of the first group of downlink transmissions and thesecond group of downlink transmissions; determine the first group-basedacknowledgment feedback associated with the first group of downlinktransmissions and the second group-based acknowledgment feedbackassociated with the second group of downlink transmissions; format thefirst group-based acknowledgment feedback and the second group-basedacknowledgment feedback into a combined feedback report; and transmitthe combined feedback report to the base station in the first uplinktransmission.
 23. The apparatus of claim 22, wherein the instructions toformat are executable by the processor to cause the apparatus to: appendthe second group-based acknowledgment feedback to the first group-basedacknowledgment feedback based at least in part on a first group index ofthe first group-based acknowledgment feedback having a lower index valuethan a second group index of the second group-based acknowledgmentfeedback.
 24. The apparatus of claim 22, wherein the instructions toformat are executable by the processor to cause the apparatus to: appendthe second group-based acknowledgment feedback to the first group-basedacknowledgment feedback based at least in part on a request for thesecond group-based acknowledgment feedback being received in downlinkcontrol information associated with the first group of downlinktransmissions.
 25. An apparatus for wireless communications at a userequipment (UE), comprising: means for receiving a first downlink controlinformation transmission from a base station that provides a first setof group-based acknowledgment feedback parameters, wherein the first setof group-based acknowledgment feedback parameters includes a first groupindicator for a first group of downlink transmissions, and a firstfeedback timing that indicates a first uplink transmission is to includea first group-based acknowledgment feedback associated with the firstgroup of downlink transmissions; means for receiving a second downlinkcontrol information transmission from the base station that provides asecond set of group-based acknowledgment feedback parameters, whereinthe second set of group-based acknowledgment feedback parametersincludes a second group indicator for a second group of downlinktransmissions, and a second feedback timing that indicates the firstuplink transmission is to include one or more of the first group-basedacknowledgement feedback or a second group-based acknowledgment feedbackassociated with the second group of downlink transmissions; and meansfor determining, based at least in part on the first feedback timing andthe second feedback timing, that the first uplink transmission is toinclude both the first group-based acknowledgement feedback and thesecond group-based acknowledgment feedback.
 26. The apparatus of claim25, further comprising: means for receiving one or more downlinktransmissions of the first group of downlink transmissions and thesecond group of downlink transmissions; means for determining the firstgroup-based acknowledgment feedback associated with the first group ofdownlink transmissions and the second group-based acknowledgmentfeedback associated with the second group of downlink transmissions; andmeans for transmitting the first group-based acknowledgement feedbackand the second group-based acknowledgment feedback to the base stationin the first uplink transmission.
 27. The apparatus of claim 25, whereinnone of the first set of group-based acknowledgment feedback parametersor the second set of group-based acknowledgment feedback parametersinclude an explicit indication that requests feedback of another groupof downlink transmissions.
 28. The apparatus of claim 27, wherein themeans for the determining further comprise: means for determining thatboth the first feedback timing the second feedback timing indicate asame uplink transmission slot.
 29. The apparatus of claim 25, whereinthe means for the determining further comprise: means for identifying afirst request field value in the first set of group-based acknowledgmentfeedback parameters that indicates a request for only the first group ofdownlink transmissions, and a second request field value in a subsequentdownlink control information transmission associated with the firstgroup of downlink transmissions that indicates a request for both thefirst group of downlink transmissions and the second group of downlinktransmissions; and means for determining that the first uplinktransmission is to include both the first group-based acknowledgementfeedback and the second group-based acknowledgment feedback based atleast in part on the second request field value.
 30. A non-transitorycomputer-readable medium storing code for wireless communications at auser equipment (UE), the code comprising instructions executable by aprocessor to: receive a first downlink control information transmissionfrom a base station that provides a first set of group-basedacknowledgment feedback parameters, wherein the first set of group-basedacknowledgment feedback parameters includes a first group indicator fora first group of downlink transmissions, and a first feedback timingthat indicates a first uplink transmission is to include a firstgroup-based acknowledgment feedback associated with the first group ofdownlink transmissions; receive a second downlink control informationtransmission from the base station that provides a second set ofgroup-based acknowledgment feedback parameters, wherein the second setof group-based acknowledgment feedback parameters includes a secondgroup indicator for a second group of downlink transmissions, and asecond feedback timing that indicates the first uplink transmission isto include one or more of the first group-based acknowledgement feedbackor a second group-based acknowledgment feedback associated with thesecond group of downlink transmissions; and determine, based at least inpart on the first feedback timing and the second feedback timing, thatthe first uplink transmission is to include both the first group-basedacknowledgement feedback and the second group-based acknowledgmentfeedback.